Question Library

(a) You are provided with a battery, an ammeter, a voltmeter, a resistance box, a key and connection wires. (i) Set up circuit as shown in the diagram above. (ii) With the key opened, measure and record the e.m.f. E\(_o\) of the battery (iii) With the key closed, select the resistance R=1 on the resistance box. Read and record the current, 1\Omega. (iv) Evaluate I\(^{-1}\). (v) Repeat the procedure for five other values of R=2\Omega,3\Omega, 4\Omega, 5\Omega, and 6\Omega. In each case, record I and evaluate I\(^{-1}\) results. (vii) Plot a graph with R on the vertical axis and I\(^{-1}\) on the horizontal axis. (Viii) Determine the slope, s, of the graph. (ix) Determine the intercept C, On the vertical axis. (x) State two precautions taken to ensure accurate results. (b)(i) Define potential difference in an electric field. (ii) A piece of resistance wire of diameter 0.2 mm and length 25 cm has a resistance of 7\Omega. Calculate the resistivity of the wire of the battery. [ \pi = 22\7]

A 2H inductor has negligible resistance and is connected to a \(\frac{50}{\pi}\) Hz A.C supply. The reactance of the inductor is?

(a) You are provided with a battery, an ammeter, a voltmeter, a resistance box, a key and connection wires. (i) Set up circuit as shown in the diagram above. (ii) With the key opened, measure and record the e.m.f. E\(_o\) of the battery (iii) With the key closed, select the resistance R=1 on the resistance box. Read and record the current, 1Ω. (iv) Evaluate I\(^{-1}\). (v) Repeat the procedure for five other values of R=2Ω,3Ω, 4Ω, 5Ω, and 6Ω. In each case, record I and evaluate I\(^{-1}\) results. (vii) Plot a graph with R on the vertical axis and I\(^{-1}\) on the horizontal axis. (Viii) Determine the slope, s, of the graph. (ix) Determine the intercept C, On the vertical axis. (x) State two precautions taken to ensure accurate results. (b)(i) Define potential difference in an electric field. (ii) A piece of resistance wire of diameter 0.2 mm and length 25 cm has a resistance of 7Ω. Calculate the resistivity of the wire of the battery. [ \pi = 22\7]

The length of an iron bar is 100cm at 20°C. At what temperature will its length increase by 0.01%? [Linear expansivity of iron = 1.2 x 10\(^{-5}\)°C]

Which of the following machines does not apply the lever principle?

Two divers G and H are at depths 20m and 40m, respectively below the water surface in a lake. The pressure on G is p\(_1\) while the pressure on H is P\(_2\), If the atmospheric pressure is equivalent to 10m of water, then the value of P\(_2\)/P\(_1\) is?

Two identical cups containing the same volume of water at 45°C and 5°C, are left in a room at 25°C. Which of the following graphs correctly illustrates the variation of temperature with time?

An electrical device has 50 turns in its primary coil and 20 turns in the secondary coil. The device can be a\an?

Which of the current-voltage characteristics shown above is that exhibited an ohmic conductor?

In an electric circuit, an inductor of inductance 0.5 H and resistance 50\(\Omega\) is connected to an alternating current source of frequency 60 Hz. Calculate the impedance of the circuit.

An image formed on a screen is always?

A ray of light traveling from glass into ethyl alcohol is incident at the boundary at an angle of incidence 30\(^o\). Calculate the angle of refraction. [Refractive index of glass =1.5; refractive index of ethyl alcohol = 1.36]

If a source of solid is moving, a stationary listener will hear a sound of different frequency. This is called?

What factors determine the frequency of a note emitted by a vibrating string?

The diagram above illustrates a beam of parallel rays from a distant object O, incident on one side of the total reflecting prism. Which diagram does not represent the correct path of the beam when it emerges from the prism?