Practicals

Question 1

IR Absorption Practical

Answer 1

1. Set up an infrared (IR) source and an IR detector facing each other.
2. Place different materials (e.g., glass, plastic, water) between the IR source and detector.
3. Turn on the IR source and measure the IR radiation detected without any material.
4. Insert the material and measure how much IR radiation passes through it.
5. Compare readings to see how much IR is absorbed by each material.
6. Record results and conclude which materials absorb or block IR radiation the most.

Question 2

Springs Practical

Answer 2

1. Hang a spring vertically and measure its original length (unstretched).
2. Add a small weight to the spring and measure the new length.
3. Increase the weight step-by-step, measuring the length each time.
4. Calculate the extension (new length - original length) for each weight.
5. Plot a graph of force (weight) vs extension to check if it’s a straight line.
6. Identify the spring constant from the graph’s gradient (force/extension).

Question 3

Newton’s 2nd Law Practical

Answer 3

1. Set up a trolley on a low-friction track with a pulley at one end.
2. Attach a string over the pulley to a hanging mass (weight).
3. Measure the total mass of the trolley plus any added masses.
4. Release the system and use a stopwatch to time the trolley’s acceleration over a known distance.
5. Calculate acceleration using distance and time (a = 2d/t²).
6. Repeat with different masses and forces, then plot force vs acceleration to see the direct relationship (F = ma).

Question 4

Waves Practical

Answer 4

1. Set up a ripple tank or a slinky to create waves.
2. Generate waves using the wave source or hand movements.
3. Observe wave properties such as reflection, refraction, or diffraction.
4. Measure the wavelength using a ruler or by counting wave crests over a distance.
5. Measure the frequency by counting the number of waves passing a point in a set time.
6. Calculate wave speed using the formula speed = frequency × wavelength.