physics-scholars

[physics-scholars]

Popular Physics Projects for Class 12

Since you do not require to make hi-tech projects during in 12th class, simple and easy projects would be less time-consuming and easier to explain. Electric cars and electric motors are two of the most common projects or physics project topics. Given below are the details about them:

Electric Car

Making an electric car for your Physics project for class 12th will set you apart from your classmates. It is easy to make and fascinating to see it work which makes it a perfect option for a project. The electric car works on a simple principle where the transmission of force from the motor to a wheel is carried through two gears and the use of rubber bands is made which act as a belt. You will get to explore various concepts of physics like Aerodynamics, Conversion of Energy, and electric circuits besides design while working on the project. 

Materials Required: A Plastic Board for Car Chassis; 4 Wheels; 4 Tire Rings; Battery Holder; Battery; Motor Mount; Electric Motor; Rubber Bands; Transmission Pulley; Screws; Paper Clips; Straw.

Electric Motor

Electric Motor is one of the most common and basic projects that you can think of. Though the concepts involved in the motor are complex but making an electric motor is relatively easy. With just a requirement of a coil of wire, a magnet, and a power source, it is a preferred choice for your Physics Project for Class 12 if you have limited time. 

Materials Required: Insulated Wire; Battery; Small Circular Magnet; Electric Tape; Modelling Clay; 2 Metal Sewing Needles; Knife.

How to Create a Visual Doppler

Aim: The following experiment is conducted to check what happens to sound waves by creating a visual model of what happens when a vehicle passes by. 

Theory: The explanation for the Doppler effect is that each successive wave crest is produced from a position closer to the observer than the crest of the previous wave, as the source of the waves is heading towards the observer. A visual simulation of what happens to the sound waves is created by this project to make them sound very different as the vehicle approaches than that when it exits.

Requirements: Ruler, Scissors, Tape, Toy car, Two pieces of coloured construction paper, Some plain paper, and a marker or a camera. 

Buoyancy 101

Aim: The following experiment is to check and determine whether a rise in water density would cause a boat hull to sink deeper in the water to an observable degree as its temperature is elevated from 5 degrees C to 95 degrees C.

Theory: This showed that increasing water temperature allows water molecules to move further out, decreasing upthrust in turn, and causing more water to be displaced by a floating mass as its buoyancy is decreased. If the water molecules spread outward due to high temperature, a large rise in water temperature can produce a noticeable difference in the water’s surface or even a small floating-point

Requirements: 10 Identical Styrene Model Boats, 128 grams of steel, and a Digital Thermometer

Heat Transfer in an Incandescent Lamp

Aim: How much of the electrical power supply of an incandescent lamp is lost by thermionic emission from the filament? If these damages are large, the operational performance of incandescent lamps could be substantially increased by their elimination.

Theory: The power output can be decomposed into thermionic emission and thermal-radiation elements using electricity, filament temperature, and ambient temperature details. The conduction is sequentially dependent upon the temperature of the filament (Fourier’s Law), but the exposure is proportional to the fourth power of the temperature of the filament (Stefan-Boltzmann Law).

Requirements: 25-watt evacuated light bulb, programmable power supply, two high-precision digital meters, and a precise digital thermometer.

Insulation Value

Aim: The experiment is to equate straw insulation with traditional forms of insulation, which are fibreglass and rigid foam panels, which are widely used today.

Theory: The most critical element in building an energy-effective contribution is adequate insulation. Insulation will hold the heat inside during cold days. Isolation will trap the sun outdoors on hot days. Insulation materials are structures that avoid the transmission of heat from a house inside and outside. To insulate walls, floors, and pipes, various materials may be used.

Requirements: Speakers, Insulation, and Digital Thermometer

Observations of Gas in the Infrared Spectrum

Aim: This project aimed to research the effect of gas chemical properties on its ability to process and transmit infrared radiation ts the transmission of infrared light. The primary aim was to mask a transmissive gas heating element.

Theory: The molecular structure of gas that specifically influences transmissivity in the infrared spectrum is confirmed by the evidence from both forms of the est. The air has high absorption zones, allowing areas of low transmittance that caused some obstructing in the infrared spectrum.

Requirements: PVC pipe, Spectroradiometer, 8-12 micron infrared camera with digital imagery, Blackbody, and gases.

Marvelous Magnetics

Aim: The purpose of this experiment was to decide how diamagnetism could influence levitation using graphite, paper, plastic, aluminium foil, or no substance.

Theory: IAbouthow many man-made objects today use magnetism or even diamagnetism, this study may even interact with the Earth. The world’s fastest train, for instance, is in Japan and runs on magnetism.

Requirements: Levitation Pedestal, Graphite, Adjustment Screw, Paper, Aluminum foil, and Plastic in Place of the Graphite. 

Long and Short Wavelength Colors

Aim: The aim of the project is that the houses were painted in both solid colours (red, blue, green, and orange) and mixed colours (red/blue and green/orange), this project examined the interior and exterior temperatures of houses and their insulation rates.

Theory: Data revealed that the order of internal temperature readings from peak to lowest matched the wavelengths of colour from longest to shortest fairly closely. Combination colour houses fell between their stable counterparts in general. Exterior temperature data shows that followed by red, red/blue, grey, blue, orange, and control, the green/orange house was the warmest. The highest insulation rate, followed by green, green/orange, red/blue, red, orange, and control, was obtained from the blue home.

Requirements: Oil paints, Control house painted white, and Digital and Infrared Thermometers.

Use and Impact of Recycled Materials for Thermal Insulation

Aim: Fiberglass, pine shavings, polystyrene, polyurethane, cellulose, perlite, polyethene foil, or bubble wrap where the goal of this experiment is to find which recycling process would be an effective electricity insulator.

Theory: This could be an asset in the summer, but even time would be spent on heating the house in the winter. It also took a bit longer than the other materials to cool fibreglass and only averaged around 12 minutes to heat it. As it warmed easily and also trapped heat to save energy, fibreglass was by far the most powerful insulator.

Requirements: Particle Board, Digital thermometer, Light Bulb, and Cardboard boxes. 

Hydro Power

Aim: The following project is conducted to learn about the first-hand force of water.

Theory: At the foot of dams, hydropower plants are designed to take advantage of higher water pressure at the edge of a dam. The excess water is funnelled into a tube called a penstock into the dam. The water is then concentrated on a turbine’s blades. The water pressure of the water transforms the engine, and a power generator turns the turbine.

Requirements: Half gallon paper milk carton, Gallon of Water, Awl or 10p nail, Masking Tape, Ruler, Magic Marker, Pair of Scissors and Pad of Paper and Pencil to Make Notes

Salt Water vs Tap Water

Aim: This experiment would be about magnets and water. Since water is diamagnetic, I used the magnets to transfer water, which means it appears to move further from magnets and electromagnets. A cookie tray with the magnets equally spread along the inside circumference of it.

Theory: Someone who studies water is a hydrologist. The study of the dynamics of electrically conducting fluids is called magnetohydrodynamics (MHD for short). One of them is salt water. You could levitate a frog if you had a powerful enough magnet. Diamagnetic and paramagnetic are also compounds. In addition, this may be the data that I require. To see whether the water is flowing or not, I would have to use rubber duckies or food colouring

Requirements: Rubber, Magnets, Angel food pie tin, Food colouring Timer, and Tape.

Investigatory Project Physics Project for Class 12: CBSE Suggestions

List of 50 Physics Project Topics for Class 12

Besides a motor and electric car, there are several other concepts that you can set your project on. Depending on the time and the available resources, you can choose a project of your choice. Given below in a table are some of the ideas for the physics project topics for class 12th:

S.No.Physics Project Topic1.How to Create a Visual Doppler2.Buoyancy 1013.Heat Transfer in an Incandescent Lamp4.Insulation Value5.Observations of Gas in the Infrared Spectrum6.Marvelous Magnetics7.Long and Short Wavelength Colors8.Use and Impact of Recycled Materials for Thermal Insulation9.Hydro Power10.Salt Water vs Tap water11.Hooke’s Law12.Proving Universal Gravitation by Warping Space-Time13.Newton’s Third Law of Motion14.The Comparison of Thermal Conductivity for Different Metals15.Brass Instruments and Artificial Lips16.An Analysis of Black Hole Thermodynamics17.Marvelous Magnetics18.Measurement of True Noon Time19.Measuring the Speed of Light20.Blackbody Thermal Emission21.Changing the Speed of Light22.Chemiluminescence23.Colour vs. Heat Absorption24.AC Generator25.Automatic Electric Train Barrier26.Light Dependent Resistance27.Rectifier28.Photoelectric Effects29.Effect of Tension on The Pitch of a String30.Effect of Pressure on Ball Bounce Height31.Effect of Mass on Terminal Velocity32.Effect of Mass on Terminal Velocity33.Effect of Pressure on Water Velocity34.Foam Thickness and Sound Attenuation35.How Accurate is Parallax36.Impact of Different Color Filters on the Energy of a Laser Beam37.Neuronal Nonlinear Dynamics38.Effect of Sugar Density on the Refractive Index of Water39.Nonlinear Oscillations in Mechanical Systems40.How Do Gases Behave in the Infrared Spectrum41.Verification of Archimedes Principle42.Hiding in Plain Sight43.Heat Transfer in an Incandescent Lamp44.Light Reflection and Refraction of Liquids45.Insulation Value46.Kinetic Energy47.Murray’s Principle of Minimum Work48.Long and Short Wavelength Colors49.Living Color50.Magnetic Force

Physics Project for Class 12 on Electromagnetic Induction and Alternating Currents

To study the idea of a full-wave bridge rectifier and the idea of a coil’s self-inductance

To Research the Self-Designed Transformer Concept

To Research and Measure the AC Current’s Strength

To Research the AC/DC Converter (Full Wave Rectifier)

To investigate the magnetic induction in an AC generator

To examine how input and output voltage relate to one another

Physics Project for Grade 12: To Investigate the Tangent Galvanometer

A circuit using four diodes to provide full-wave rectification converts an AC voltage to a pulsating DC voltage and is used to study the many factors affecting internal resistance or EMF.

Physics Project for Class 12 on Current Electricity

To learn about resistance and the Ohms law

To establish the RC circuit’s time constant

To investigate the idea of electrical resistance variation

The Future of Electricity: A Study of Wireless Energy

To research and discover novel electricity-generating methods

To investigate the parallel and series combinations of resistors

Studying the operation of the Wheatstone Bridge Circuit and its use

To Research Current Variation Using an LDR: 12th-grade physics projects

To investigate the impact of different temperatures on the resistivity of insulators

To determine how the following factors affect an avalanche cell’s internal resistance 

Physics Project for Class 12 on Electrostatics

To investigate how a series of capacitors charges and discharges

To Research and Build a Capacitor Storage Circuit LED

To Research and Build a Capacitor Charge Oscillator Circuit to Research the Electric Dipole Moment: Physics Project Subjects

To learn about Coulomb’s law of forces at two points

To research the electric field and the superposition principle

To investigate the dipole’s torque in a consistent electric field

To research dielectric materials for cutting-edge applications

Project for Physics class 12: To Illustrate The Operation Of An Electrolytic Capacitor Using Its Charging And Discharging With The Aid Of An Audio Oscillator

To examine and contrast the two capacitors when used in series and parallel

Physics Project for Class 12 on Magnetic Effects of Current and Magnetism

To research the impact of applied voltage and magnetic field

To Research the Bar Magnet as a Comparative Solenoid

To research using magnetic levitation in elevators

Physics Investigational Project on the Moving Coil Galvanometer to Study the Magnetic Force on the Current-Carrying Conductor Physics Experiment with Galvanometer to Voltmeter

To investigate the torque that a current loop experiences in a consistent magnetic field.

Physics projects for the 12th grade: To Study the Magnetic Properties of Materials

To study the magnetic force between two parallel current-carrying conductors by experimenting with magnetic field lines surrounding them.

Physics Project for Class 12 on Optics

How Does Distance Impact Light Intensity?

Study of the Impact of Space-Time Curvature

Changing the Speed of Light: Research and Analysis

To study the idea of reflection in the concave mirror, are there more cosmic rays at higher altitudes?

To Research the Reconstruction of the Cosmic Ray Shower Array To Research Light Refraction in a Rectangular Glass Slab

To Research and Observe the Gas in the Infrared Spectrum to Showcase the Total Internal Reflection Phenomenon

Physics Project for Class 12 on Oscillations and Waves

Some of the physics project ideas or physics project topics on Oscillations and Waves are mentioned below.

To research the laws governing the sound reflection

Utilizing sound to gauge the temperature

To research and calculate the density of solids

To Calculate the Sound Speed at Room Temperature

To Measure the Speed of Sound at Room Temperature and Study the Doppler Effect and Fiber Gyroscope

To Research and Test the Sound Decay in Various Gases

To investigate mechanical systems’ nonlinear oscillations

To learn the distinction between longitudinal waves and transverse waves, ethnic groups’ voice frequencies were studied and analyzed.

Modern Physics Project Topics for Class 12

Some of the modern physics project topics for class 12 are listed below.

Modern Physics and the Study of the Photoelectric Effect

To research the assumptions and constraints of the Bohr atomic model

To learn about Henry Moseley’s law and its applications

To investigate the de Broglie Wavelength of Matter Waves Concept and Related Problems

To learn about the several forms of radioactivity in modern physics

General Topics for Physics Project for Class 12

Some of the general physics project topics for class 12 are listed below.

To Study the Effect of Pressure on the Water Velocity

Charge Induced on Two Identical Stryo Foam Balls

Study the Solar Cells: Physics Projects for Class 12

To Study the Electrochemical Cell (Primary Cell)

To Construct A Circuit of Two Transistor Oscillator

To Study the Zero Gravity Elevator Physics Experiment

[physics-scholars]

Ms. Sathya

In earth if it's one sec is that same in space also.... will our watch show same tym in space also.... how this varies..❓

In space, time passes differently than on Earth due to the effects of relativity. The theory of relativity explains that time is relative and not absolute. It means that time can be different for two observers depending on their relative motion and gravitational potential.

The difference in time between Earth and space is due to time dilation. Time dilation is the difference in elapsed time as measured by two clocks, either due to a relative velocity between them (special relativity), or a difference in gravitational potential between their locations (general relativity).

For example, if you were to travel at a high speed in space, time would appear to pass more slowly for you than it would for someone on Earth. Similarly, if you were to orbit a massive object like a planet or star, time would appear to pass more slowly for you than it would for someone far away from the object.

Therefore, if you were to take a watch from Earth into space and compare it with another watch that remained on Earth, you would find that the two watches show different times after some time has passed. The difference in time between the two watches would depend on the relative motion and gravitational potential.

[physics-scholars]

Laxmi Sowjanya

Q

can we consider cyan magenta as primary colours??

A

Cyan, magenta, and yellow are considered primary colors in the subtractive color model used in printing and color mixing. In this model, they are used as primary colors because they can be combined to create a wide range of other colors. This is different from the additive color model, where red, green, and blue are the primary colors used for displays like computer screens.

[physics-scholars]

Saurabh Tiwari

Q:

Is there any difference between uniform potential and equipotential surface ?

A:

Yes, there is a difference between uniform potential and equipotential surfaces.

Uniform potential refers to a situation where the electric potential is the same at all points within a defined region of space. In other words, there is a constant potential value throughout that region. This typically occurs when there is a uniform electric field present, such as between two parallel plates with a constant potential difference.

On the other hand, an equipotential surface is a surface in space where all points on that surface have the same electric potential. In other words, it is a surface where the electric potential is constant. Equipotential surfaces are always perpendicular to the electric field lines.

In short:

Uniform potential refers to a situation where the potential is the same at all points within a region, while an equipotential surface is a surface where the potential is constant at all points on that surface.

[physics-scholars]

Physics

How would you introduce electro magnetic induction to your students in class 12 ?

1. Introduction to Electromagnetic Induction

Teacher: Good morning, class! Today, we're going to dive into a fascinating topic of physics called electromagnetic induction. Electromagnetic induction is a fundamental concept discovered by the renowned scientist Michael Faraday in the early 19th century. This concept plays a crucial role in understanding various technological advancements, from power generation to electric motors and transformers. So, let's explore this concept together!

Teacher: To begin, let's break down the term "electromagnetic induction." "Electro" refers to electricity, while "magnetic" relates to magnets or magnetic fields. Induction, in this context, implies the creation of a current or voltage in a conductor when it is exposed to a changing magnetic field. In simpler terms, it's the process of generating electricity by moving a magnet near a conductor or by varying the magnetic field through a conductor.

Teacher: Now, let's discuss the basic principles of electromagnetic induction. To induce an electric current, we need two key components: a magnetic field and a conductor. A conductor is usually a wire made of a conductive material like copper or aluminum. When a magnetic field interacts with a conductor, it causes the electrons within the conductor to move, creating an electric current.

Teacher: Now, let's conduct a small experiment to visualize electromagnetic induction. I have here a coil of wire connected to a galvanometer, which is an instrument used to measure electric current. I will move a bar magnet back and forth inside the coil. Watch what happens to the galvanometer.

[Teacher demonstrates the experiment, showing the galvanometer deflecting, indicating the presence of an electric current.]

Teacher: As you can see, when I move the magnet inside the coil, we observe a deflection in the galvanometer. This deflection indicates the flow of an electric current in the coil. When the magnet moves, it creates a changing magnetic field around the coil, which, in turn, induces an electric current in the wire.

Teacher: This experiment demonstrates Faraday's law of electromagnetic induction, which states that the magnitude of the induced electromotive force (EMF) or voltage in a circuit is directly proportional to the rate of change of magnetic flux through the circuit. Magnetic flux refers to the total number of magnetic field lines passing through a given area.

Teacher: Moreover, Faraday's law also tells us that the direction of the induced current will be such that it opposes the change that caused it. This concept is known as Lenz's law. It helps us understand why the induced current flows in a specific direction.

Teacher: Now that we have a basic understanding of electromagnetic induction, we can explore its applications in various fields, such as power generation in electrical generators, operation of electric motors, transformers, and even wireless charging technologies.

Teacher: To summarize, electromagnetic induction is a fundamental principle in physics, describing the generation of an electric current in a conductor when exposed to a changing magnetic field. It was discovered by Michael Faraday and has since revolutionized our understanding of electricity and magnetism.

Teacher: I encourage you all to explore this concept further through hands-on experiments, research, and practical applications. Understanding electromagnetic induction will open doors to innovative technologies and deepen our knowledge of the interconnectedness between electricity and magnetism.

Teacher: That's all for today's introduction to electromagnetic induction. I hope you found it intriguing! If you have any questions, please feel free to ask.

2. Expt. Demonstration:

Some siimple demonstration you can try to further illustrate electromagnetic induction:

Materials needed:

1. A coil of wire (you can make one by wrapping several loops of insulated wire around a cylindrical object like a pen)

2. A bar magnet

3. A galvanometer or a multimeter set to measure voltage

4. Connecting wires

Procedure:

1. Connect the ends of the coil of wire to the galvanometer or multimeter.

2. Place the bar magnet near one end of the coil without touching it.

3. Observe the galvanometer or multimeter reading.

You should notice that when you move the magnet closer to the coil or away from it, the galvanometer or multimeter will detect a change in voltage or current. This change indicates the induction of an electric current in the coil due to the changing magnetic field created by the magnet.

You can further explore the demonstration by trying different scenarios, such as moving the magnet at different speeds, using different strengths of magnets, or reversing the direction of the magnet's movement. These variations will help you observe how the induced current changes in response to different magnetic field conditions.

3. Activities:

These are a few activities you can try to deepen your understanding of electromagnetic induction:

1. Build an Electromagnetic Induction Demonstrator:

Materials needed: A coil of wire, a bar magnet, a galvanometer or multimeter, connecting wires, a wooden board.

Procedure:

- Mount the coil of wire securely on the wooden board.

- Connect the ends of the coil to the galvanometer or multimeter.

- Place the bar magnet near the coil without touching it.

- Move the magnet back and forth or rotate it near the coil while observing the galvanometer or multimeter readings.

- Observe how the galvanometer or multimeter detects changes in voltage or current as you vary the magnet's position and movement.

2. Simple Electric Generator:

Materials needed: A coil of wire, a strong magnet, a small LED or a light bulb, connecting wires.

Procedure:

- Create a coil by wrapping several loops of wire around a cylindrical object.

- Connect the ends of the coil to the LED or light bulb.

- Hold the magnet near the coil without touching it.

- Rotate the magnet quickly inside the coil.

- Observe the LED or light bulb lighting up, indicating the generation of electricity through electromagnetic induction.

3. Investigate the Factors Affecting Induced Current:

Materials needed: A coil of wire, a magnet, a stopwatch, a galvanometer or multimeter, connecting wires.

Procedure:

- Connect the coil of wire to the galvanometer or multimeter.

- Hold the magnet near the coil.

- Start the stopwatch and move the magnet towards and away from the coil at a constant speed for a specific time period.

- Observe and record the galvanometer or multimeter readings.

- Repeat the experiment, changing factors such as magnet strength, speed of movement, or number of coil loops.

- Analyze and compare the results to see how these factors affect the induced current.

Remember to approach these activities with caution and prioritize safety. Ensure that electrical connections are secure, and be mindful of any sharp objects or moving parts. Always follow proper safety guidelines and adult supervision when necessary.

These activities will provide you with hands-on experiences and help reinforce your understanding of electromagnetic induction. Have fun exploring!

[physics-scholars]

Ashish

Q. Why does apparent depth of water decrease when we view obliquely.

Any one having correct explanation or any mathematical proof please share?.

The apparent depth of water decreases when viewed obliquely because of the phenomenon of refraction. When light travels from one medium to another, its speed changes and it bends (refracts) at the boundary between the two media. In the case of water, the speed of light is slower than in air, so when light enters the water at an angle, it bends towards the normal (an imaginary line perpendicular to the surface of the water).

As a result, objects underwater appear to be shifted from their actual position. The amount of shift depends on the angle of incidence (the angle between the incident ray of light and the normal) and the refractive index of the two media. When viewed obliquely, the angle of incidence is greater, causing a greater amount of shift and making the object appear shallower than it actually is.

Mathematically, we can use Snell's law to calculate the amount of refraction:

n1 sinθ1 = n2 sinθ2

where n1 and n2 are the refractive indices of the two media, θ1 is the angle of incidence, and θ2 is the angle of refraction. As θ1 increases, θ2 also increases, causing a greater amount of refraction and a shallower apparent depth.

[physics-scholars]

Syed Ibrahim

A man with normal near point (25 cm) reads a book with small print using a magnifying glass: a thin convex lens of focal length 5 cm.

(a) What is the closest and the farthest distance at which he should keep the lens from the page so that he can read the book when viewing through the magnifying glass?

▪️

The magnification produced by the lens is given by:

m = 1 + (d/f)

where d is the distance between the lens and the object (in this case, the page of the book), and f is the focal length of the lens.

To find the closest distance at which the man can read the book, we need to use the formula for near point:

1/25 + 1/d = 1/f

Substituting f = 5 cm, we get:

1/25 + 1/d = 1/5

Solving for d, we get:

d = 6.25 cm

Now we can use the magnification formula to find the magnification produced by the lens when it is held at this distance:

m = 1 + (6.25/5) = 2.25

This means that the image of the text on the page will appear 2.25 times larger than it would without the lens.

To find the farthest distance at which the man can read the book, we need to use the formula for far point:

1/∞ + 1/d = 1/f

Simplifying, we get:

1/d = 1/5

Solving for d, we get:

d = 5 cm

Now we can use the magnification formula to find the magnification produced by the lens when it is held at this distance:

m = 1 + (5/5) = 2

This means that the image of the text on the page will appear 2 times larger than it would without the lens.

Therefore, the closest distance at which he should keep the lens from the page is 6.25 cm, and the farthest distance is 5 cm.

[physics-scholars]

Ms. Sathya

What is unfilled orbitals... Splitting of electrons in energy band❓

Unfilled orbitals refer to the atomic orbitals within an atom that do not have electrons occupying them. In an atom, electrons occupy specific energy levels or orbitals around the nucleus. When an atom is in its ground state, all the lower energy orbitals are filled with electrons before any higher energy orbitals are occupied. Unfilled orbitals are those that are available for electrons to occupy if the atom gains or loses electrons, or if it interacts with other atoms.

On the other hand, the splitting of electrons in an energy band refers to the phenomenon that occurs when atoms come together to form a solid material or crystal lattice. In a solid, the energy levels of the individual atoms' orbitals combine to form a continuous range of energy levels called an energy band. These energy bands can be separated by energy gaps known as band gaps.

When the atoms are close together in a crystal lattice, their orbitals start to overlap. This overlapping of orbitals leads to the splitting of energy levels. In particular, when many atoms are combined, the atomic orbitals from each atom mix and form molecular orbitals that span the entire crystal. This results in the formation of energy bands.

In a solid material, the electrons are distributed among these energy bands. The lower energy bands, known as valence bands, are usually filled with electrons, while the higher energy bands, known as conduction bands, are partially or completely empty. The splitting of electrons in energy bands is crucial for understanding various properties of solid materials, including their electrical conductivity and optical behavior.

[physics-scholars]

Anandha Raja

How to find direction of EMW (+axis and -axis)....Any tricks?

▪️

To determine the direction of an electromagnetic wave (EMW), you can use the right-hand rule. The right-hand rule is a common method used in physics to determine the direction of a magnetic field, electric current, or the resulting force in a magnetic field.

1. Extend your right hand and orient your thumb, index finger, and middle finger perpendicular to each other. The thumb, index finger, and middle finger should be at right angles to one another.

2. Assign the following directions to each of your fingers:

- Thumb: Points in the direction of propagation of the EMW or the positive direction.

- Index finger: Points in the direction of the electric field (E-field) vector.

- Middle finger: Points in the direction of the magnetic field (B-field) vector.

3. Now, place your hand in a way that aligns the index finger, middle finger, and thumb with the corresponding directions of the EMW. If you know the direction of either the electric field or the magnetic field, you can determine the direction of the other field and the direction of propagation using the right-hand rule.

The electric and magnetic fields in an EMW are perpendicular to each other and both are perpendicular to the direction of propagation. By knowing the direction of any two fields, you can find the third.

[physics-scholars]

Shrikalaravi

What is snells window❓

Snell's window, also known as Snell's circle or the "zone of silence," refers to a phenomenon that occurs when observing underwater objects from above the water's surface. It is named after the Dutch mathematician and physicist Willebrord Snell, who made significant contributions to the understanding of light and optics.

When light passes through the interface between two different media, such as air and water, it undergoes refraction, which causes the light rays to change direction. Snell's window occurs when an observer, positioned above the water's surface, views objects underwater at a specific range of angles.

The phenomenon is characterized by a circular region on the water's surface through which an observer can see objects underwater more clearly. This circular region appears as a window or a patch of lighter or brighter water compared to the surrounding area. The size and shape of Snell's window depend on various factors, including the observer's position, the depth of the water, the angle of observation, and the refractive index of the media involved.

Snell's window is particularly noticeable when the observer is viewing objects underwater from a shallow angle, such as when looking down from a boat or standing at the edge of a swimming pool. The window provides a clearer view of underwater objects within its boundaries, while objects outside the window appear distorted or invisible due to the bending of light rays at the air-water interface.

It's important to note that Snell's window is a visual phenomenon and does not affect the behavior of light itself. It is a result of the way light refracts at the air-water interface, and it can be observed in any situation where light passes through different media with different refractive indices.

[physics-scholars]

Saurab Tiwari

Would you please share the information that how the smartwatch measures the heart rate of the human body?

Working function of a smartwatch?

▪️

A smartwatch measures the heart rate of the human body through a process called photoplethysmography (PPG). The smartwatch uses a green LED light to illuminate the skin on the wrist and a photodiode sensor to detect changes in the amount of light that is absorbed or reflected by the blood vessels. As the heart beats, blood flow increases and the amount of light absorbed or reflected by the blood vessels changes. The smartwatch then uses an algorithm to analyze these changes and calculate the heart rate. Additionally, some smartwatches also use sensors such as accelerometers and gyroscopes to detect motion and provide additional data for more accurate heart rate readings. The smartwatch also performs other functions such as displaying notifications, tracking fitness activities, and controlling other devices.

[physics-scholars]

Sengodan

Current is scalar or vector quantity?

Current is a scalar quantity. For a physical quantity to be termed a vector quantity, having magnitude and direction is not enough. The quantity should obey the laws of vector addition too. Like the triangle law or the parallelogram law. As we know, if two currents meet at a junction, the total current of the resultant current will be the algebraic sum of the two current and not the vector sum.

[physics-scholars]

Thomas

Does electronic gadgets work in wormholes?

Based on current scientific understanding, it is unlikely that electronic gadgets would work in a wormhole as the extreme conditions inside a wormhole, such as intense gravitational forces and high radiation levels, may interfere with the functioning of electronic devices. Additionally, the concept of a wormhole is still purely theoretical and has not been observed or proven to exist in reality.

[physics-scholars]

Ms. Sathya

Why are planets revolving and why does earth rotate?

Planets are revolving because of the force of gravity. Gravity is the force that attracts objects towards each other. In the case of planets, they are attracted towards the sun. The sun's gravity pulls the planets towards it, causing them to revolve around it.

The earth rotates because of its initial momentum and the conservation of angular momentum. When the earth was formed, it started rotating due to the gravitational forces acting on it. As there is no external force acting on the earth, its rotation continues due to the conservation of angular momentum. The rotation of the earth causes day and night and also affects the climate and weather patterns.

[physics-scholars]

Preeti

Pooma

[physics-scholars]

Shrikalaravi

We Learn wattles current.

The zero watt bulb can be an example for it?

Suggestion----

🔹 "Wattless current" is a term used in the context of AC (alternating current) circuits to refer to the reactive power component.

Reactive power does not perform any useful work, such as providing light or heat, but it is necessary to maintain the magnetic fields in inductive devices like motors and transformers.

The term "zero watt bulb" is not related to wattless current or reactive power. It's still not accurate to call any practical bulb a "zero watt bulb" because all light bulbs consume some power to emit light.

However, energy-efficient bulbs like LED bulbs have very low power consumption compared to traditional incandescent bulbs, and they minimize the wattless current in the circuit by reducing reactive power.

[physics-scholars]

Shrikalaravi

Does Electrocuting happens in AC or DC.

▪️Electrocution can happen with both AC (alternating current) and DC (direct current) electrical systems. The term "electrocution" refers to a fatal electric shock, and it can occur with either type of current if a person comes into direct contact with an electrically charged source. The severity of injury or danger of electrocution may vary depending on factors such as the voltage, current, and duration of exposure to the electric source.