Mandatory Physics Experiments: Mechanics, Heat, Light, Electricity

What is the definition of velocity?

Velocity is speed in a given direction.

What is the formula for acceleration?

a = (v - u) / t

What is the formula for distance when starting from rest?

s = (1/2)at²

What apparatus is used to measure velocity and acceleration?

Ticker tape, ticker timer, trolley, adjustable slope, metre stick.

What is the first step in measuring velocity and acceleration?

Run one end of the ticker tape through the ticker timer and attach it to the trolley.

What is the method to calculate time taken in the velocity experiment?

t = n / f, where n is the number of spaces between dots and f is the frequency of the timer.

What is the relationship between acceleration and force according to the theory?

The change in linear momentum of a body is directly proportional to the applied force.

What is the formula that represents the principle of conservation of momentum?

m1u + m2u = m1v + m2v

What apparatus is used to verify the principle of conservation of momentum?

Ticker tape, ticker timer, two trolleys, adjustable slope, electronic balance.

What does Boyle's Law state?

At constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure.

What is the result expected from the Boyle's Law experiment?

The graph of P vs. 1/V should be a straight line through the origin.

What is the condition for a body to be in equilibrium?

The vector sum of the forces in any direction is zero.

What apparatus is used to investigate the laws of equilibrium?

Metre stick, two spring balances, two retort stands and clamps, Newton weights, electronic balance.

What is the significance of the ticker tape in the experiments?

It helps measure the velocity of the moving body.

What precautions should be taken to reduce friction in the experiments?

Oil the wheels, incline the runway, and ensure the runway is smooth and clean.

What is the expected result when plotting force against acceleration?

A straight line through the origin.

What should be done to ensure the trolley moves with constant velocity?

Adjust the slope and ensure the string pulling the trolley is parallel to the slope.

What is the formula for momentum?

p = mv, where p is momentum, m is mass, and v is velocity.

What is the purpose of measuring the mass of the trolleys in the momentum experiment?

To calculate the total momentum before and after the collision.

What should be ignored in the velocity measurement experiment?

The first few dots on the ticker tape, as they introduce error.

How can one ensure that the mass of the system remains constant during the experiments?

By moving weights from the trolley to the scale pan.

What is the relationship between pressure and volume in Boyle's Law?

P ∝ 1/V, meaning pressure is inversely proportional to volume.

What should be done after changing the pressure in the Boyle's Law experiment?

Wait for the temperature of the gas to return to room temperature.

What is the significance of the centre of gravity in equilibrium experiments?

It helps determine the balance point of the metre stick.

What is the expected conclusion from the conservation of momentum experiment?

The total momentum before the collision equals the total momentum after the collision.

What is the method to measure the acceleration of the trolley?

Use the ticker tape and timer to measure the velocity and calculate acceleration.

What is the role of the scale pan in the acceleration experiment?

It provides the force F that causes the trolley to accelerate.

What should be done to ensure accurate measurements in the momentum experiment?

Choose dots immediately before and after the collision.

What is the formula for calculating the weight of the metre stick?

W = mg, where W is weight, m is mass, and g is acceleration due to gravity.

What is the relationship between the forces acting on a spring balance and weights in equilibrium?

The forces up equal the forces down: F1 + F2 = W + W1 + W2 + W3.

What does the sum of the moments about any point equal in a system in equilibrium?

The sum of the moments about any point is zero: F1d1 + W2s2 + W3s3 = F2d2 + W1s1.

What should the graph of P vs. 1/V look like for a body in equilibrium?

It should be a straight line through the origin.

What is the formula for the period of a simple pendulum?

T = 2π√(ℓ/g) where T is the period, ℓ is the length, and g is the acceleration due to gravity.

What is the relationship between the length of a pendulum and the square of its period?

The length of a pendulum is directly proportional to the square of the period: T² = 4π²ℓ/g.

What is the approximate value of acceleration due to gravity (g) derived from pendulum experiments?

Approximately 9.8 m/s².

What is a thermometric property?

A thermometric property is any physical property that changes measurably and uniformly with temperature.

What is the purpose of creating a calibration curve for a thermometer?

To accurately determine temperature readings by comparing the height of the liquid column to standard temperatures.

What should be done to ensure accurate readings when measuring the height of a liquid column in a thermometer?

Ensure no parallax error occurs when reading the height.

What is the specific heat capacity of water?

Approximately 4180 J/kg·K.

What is the specific heat capacity of aluminum?

Approximately 910 J/kg·K.

What is the formula for calculating heat lost or gained?

H = mc∆θ where H is heat, m is mass, c is specific heat capacity, and ∆θ is the change in temperature.

What is the specific latent heat of fusion of ice?

The amount of heat needed to change ice at 0°C to water at 0°C without changing temperature.

What precautions should be taken when measuring the specific heat capacity of water?

Ensure no heat is lost to the surroundings and that the calorimeter is well insulated.

What is the method for measuring the specific latent heat of fusion of ice?

Measure the mass of the calorimeter, add warm water, and then measure the mass after adding ice.

What is the importance of using a narrow fulcrum in experiments?

To get an accurate reading when finding the center of gravity of an object.

Why should spring balances be hung vertically during experiments?

To avoid friction and ensure readings are parallel to the weights.

What is the significance of measuring perpendicular distances in moment calculations?

To ensure accurate calculations of moments about a pivot point.

What should be done if oscillations of a pendulum become elliptical?

Start the experiment again to ensure simple harmonic motion.

What is the effect of increasing the length of a pendulum beyond 1 meter?

It becomes increasingly difficult to measure accurately, leading to larger percentage errors.

What is the first step in measuring the specific heat capacity of a metal?

Find the mass of the empty calorimeter using an electronic balance.

What is the role of a stirrer in the specific heat capacity experiment?

To ensure consistent temperature throughout the liquid.

What should be done to ensure the pendulum swings through a small arc?

Keep the angle less than 5 degrees from the vertical.

What is the purpose of using a spirit level in experiments?

To ensure that the measuring stick is horizontal for accurate readings.

What is the relationship between the mass of the calorimeter and the water in specific heat experiments?

The mass of the calorimeter plus water must be measured to calculate heat transfer.

What is the formula used to calculate the slope in the pendulum experiment?

g = 4π² · slope.

What is the significance of taking multiple readings in experiments?

To obtain more accurate and reliable results.

What is the initial step in measuring the specific latent heat of fusion of water?

Insulate the calorimeter and measure the initial temperature of the water (θI) using a thermometer.

What is the final temperature measured in the specific latent heat of fusion experiment?

The lowest temperature (θF) reached by the water after all the ice has melted.

What is the formula for calculating heat lost and gained in the latent heat of fusion experiment?

(mc∆θ)w + (mc∆θ)cal = (ml)ice + (mc∆θ)ice.

What is the specific latent heat of fusion of water?

Approximately 328341 Jkg−1K−1.

What are two basic assumptions made in the latent heat of fusion experiment?

(a) The ice cubes are at 0°C; (b) All heat needed to melt the ice is taken from the water and calorimeter.

What is the first step in measuring the specific latent heat of vaporization of water?

Find the mass of the empty calorimeter (mcal) using an electronic balance.

What is the result for the specific latent heat of vaporization of water?

Approximately 2.3 × 10^6 Jkg−1.

What is the formula used to calculate the speed of sound in air?

v = fλ, where λ = 4(ℓ + 0.3d).

What apparatus is used to measure the speed of sound in air?

Resonance tube, graduated cylinder, water, tuning forks, metre stick, Vernier callipers.

What is the conclusion regarding the speed of sound in air?

Approximately 340 ms−1.

What is the relationship between the frequency of a stretched string and its length?

The frequency is inversely proportional to its length (f ∝ 1/ℓ).

What is the relationship between the frequency of a stretched string and tension?

The frequency is directly proportional to the square root of the tension (f ∝ √T).

What is the method for measuring the frequency of a stretched string with fixed tension?

Make the wire as long as possible and measure the length (ℓ) when resonance occurs.

What is the result of the frequency vs. length graph for a stretched string?

A straight line through the origin.

What precautions should be taken when measuring the speed of sound?

Do not use tuning forks of too high frequency; ensure proper setup for resonance.

What is the significance of the end correction term in the speed of sound experiment?

It accounts for the fact that the antinode does not end exactly at the edge of the tube.

What should be done to ensure accurate results when measuring the specific latent heat of vaporization?

Lag the calorimeter well to prevent heat loss or gain from surroundings.

What is the effect of using a liquid of different density in the speed of sound experiment?

It would make no difference since almost all sound is reflected from the surface.

What is the purpose of stirring the water before reading the final temperature in the vaporization experiment?

To ensure uniform temperature throughout the water.

What is the importance of drying the steam before it enters the calorimeter?

To ensure that only steam and no water enters the calorimeter.

What is the role of the paper rider in the stretched string experiment?

It jumps off the wire when resonance occurs, indicating the correct frequency.

What is the method for varying tension in the stretched string experiment?

Adjust the tension control key while keeping the length fixed.

What is the expected outcome of the frequency vs. tension graph for a stretched string?

A straight line through the origin.

What is the primary goal of the specific latent heat experiments?

To find the amount of heat needed to change the state of a substance.

What is the significance of measuring the mass of the calorimeter plus water plus steam?

It allows for accurate calculation of heat transfer during the experiment.

What should be done to minimize heat loss during the latent heat experiments?

Ensure the calorimeter is well insulated.

What is the relationship between the frequency of a stretched string and its mass per unit length?

The frequency is constant if tension and length are fixed.

What is the effect of pre-cooling the water before adding steam in the vaporization experiment?

It results in less heat lost to the surroundings, improving accuracy.

What formula is used to calculate the focal length of a concave mirror?

f = 1/u + 1/v

What apparatus is needed to measure the focal length of a concave mirror?

Concave mirror, screen, ray box with cross threads, metre stick.

How do you find the approximate focal length of a concave mirror?

By focusing the image of a distant object on a piece of paper.

What is the method to measure the focal length of a converging lens?

Use the same formula f = 1/u + 1/v and follow similar steps as for the concave mirror.

What is the formula for calculating the refractive index of a liquid?

µ = real depth / apparent depth

What apparatus is used to measure the refractive index of water?

Plane mirror, two pins, cork, retort stand and two clamps, beaker, water.

What is Snell's Law?

sin i / sin r = n, where n is the refractive index of the second medium.

What is the purpose of tracing the outline of a prism in the Snell's Law experiment?

To measure angles of incidence and refraction accurately.

What is the grating equation used to measure the wavelength of monochromatic light?

nλ = d sin θ

What is the first step in measuring the wavelength of monochromatic light?

View the image of the light source directly opposite the collimator.

What should be done to avoid parallax error when taking measurements?

Ensure the measurement is taken directly in line with the scale.

What is the significance of averaging multiple readings in experiments?

To reduce random errors and improve accuracy.

What is the importance of ensuring a sharp image when conducting optical experiments?

A sharp image is necessary for accurate measurements of distances.

What is the role of the ray box in measuring the focal length of mirrors and lenses?

It provides a clear and consistent light source for focusing images.

In the refractive index experiment, what should be adjusted to eliminate parallax?

The height of the search pin above the mirror.

What does the slope of the graph of real depth vs. apparent depth represent?

The refractive index of the liquid.