Question Library

You are provided with a battery of e.m.f, E, a standard resistor, R, of resistance 2 \(\Omega\), a key, K, an ammeter, A, a jockey, J, a potentiometer, UV, and some connecting wires. (i) Measure and record the emf, E, of the battery. (ii) Set up the circuit as shown in the diagram above with the key open. (iii) Place the jockey at the point, U, of the potentiometer wire. Close the key and record the reading, i, of the ammeter. (iv) Place the jockey at a point T on the potentiometer wire UV such that d = UT = 30.0 cm. (v) Close the circuit, read and record the current, I, on the ammeter, (vi) Evaluate I\(^{1}\). (vi) Repeat the experiment for four other values of d = 40.0 cm, 50.0 cm, 60.0 cm and 70.0 cm. In each case, record I and evaluate I\(^{1}\). (vii) Tabulate the results (ix) Plot a graph with d on the vertical axis and I on the horizontal axis stalling both axes from the origin (0,0). (x) Determine the slope, s, of the graph. (xi) From the graph determine the value \(I_1\), of I when d = 0. (ci) Given that=s, calculate 8. (xii) State two precautions taken to ensure accurate results. (xii) Given that \(\frac{E}{\delta}\) = s, calculate \(\delta\). (b)(i) Write down the equation that connects the resistance, R, of a wire and the factors on which it depends. State the meaning of each of the symbols. (ii) An electric fan draws a current of0.75 A in a 240 V circuit. Calculate the cost of using, the fan for 10 hours if the utility rate is $ 0.50 per kWh.

If an object just begins to slide on a surface inclined at 30º to the horizontal,the coefficient of friction is?

Calculate the mass of ice that would melt when 2kg of copper is quickly transferred from boiling water to a block of ice without heat loss (specific heat capacity of copper = 400Jkg\(^{1}\)k\(^{-1}\), latent heat of fusion of ice = 3.3 x 10\(^{5}\)Jkg\(^{-1}\))

A metallic sphere is heated from 27°C to 200°C Without change of state. Which of the following changes would have resulted from the heating?

Particles of mass 10\(^{-2}\)kg is fixed to the tip of a fan blade which rotates with angular velocity of 100rad\(^{-1}\). If the radius of the blade is 0.2m, the centripetal force is?

A ball is swung in a horizontal circle of centre O with a constant speed. What is the direction of its acceleration?

A ball of mass 0.1kg is thrown vertically upwards with a speed of 10ms\(^{-1}\) from the top of a tower 10m high. Neglecting air resistance, its total energy just before hitting the ground is? (Take g = 10ms\(^{-2}\))

A man weighing 200 N runs up a staircase in 5s. If the height of the staircase is 9 m, calculate the power of the man.

The slope of the straight line displacement-time graph indicates?

Two bodies have masses in the ratio3:1. They experience forces which impart to them, acceleration in the ratio 2:9 respectively. Find the ratio of forces the masses experienced

The diagram above illustrates the velocity-time graph of a body. Calculate the distance covered by the body during the motion

A solid weighs 10.00N in air, 6N when forcefully immersed in water, and 7.0N when fully immersed in a liquid, X. Calculate the relative density of the liquid X.

A projectile is fired at an angle of 30° to the horizontal with a velocity of 40 m/s Calculate the velocity attained after 1 s. [g = 10 m/s\(^2\)]

A ball of mass 0.5kg moving at 10ms\(^{-1}\) collides with another ball of equal mass at rest. If the two balls move off together after the impact, calculate their common velocity.

A lead bullet of mass 0.05kg is fired with a velocity of 200ms\(^{-1}\) into a block of mass 0.95kg. Given that the lead block can move freely, the final kinetic energy after impact is?