A machine of efficiency 8% is used to raise a body of mass 75kg through a vertical height of 3m in 30s. Calculate the power input. (g = 10ms^-2)

• A. 9.4W
• B. 60.0W
• C. 75.0W
• D. 93.8W

A proton of wavelength \(\lambda_o\) is emitted when an electron in an atom makes a transition from a level of energy 2E. If the electron transits from \(\frac{4}{3}E_k\) to E level, determine the wavelength of the photon that would be emitted

• A. 3\(\lambda_o\)
• B. 2\(\lambda_o\)
• C. \(\frac{3}{4}\)\(\lambda_o\)
• D. \(\frac{1}{3}\)\(\lambda_o\)

Two bodies P and Q, are in thermal equilibrium, which of the following statements about the bodies is correct?

• A. the temperature of Q is higher than that of P
• B. P and Q have the same heat capacity
• C. P and Q have the same mass
• D. P and Q are at the same temperature

Absorption line spectra exhibited by atoms is a result of

• A. change in the kinetic energy of a movimg atom
• B. instability of the nucleons
• C. excitation of an electron in the atom
• D. transition of an electron from a higher to a lower energy level

A force of 40 N is applied at the end of a wire 4m long and produces an extension of 0.24mm. If the diameter of the wire is 2.00mm, calculate the;

(i) stress on the wire; (ii) strain in the wire.

The cubic expansivity of mercury is 1.8 x 10^-4K^-1 and the linear expansivity of glass 8.0 x 10^-6K^-1, calculate the apparent expansivity of mercury in a glass container

• A. 1.00 x 10^-4K^-1
• B. 1.56 x 10^-4K^-1
• C. 1.72 x 10^-4K^-1
• D. 2.04 x 10^-4K^-1

What is a projectile? Give four examples of projectiles in everyday life

The duality of matter implies that matter

• A. exists as a particle of dual composition
• B. has momentum and energy
• C. has both wave and particle properties
• D. is made up of dual materials

In the diagram below, the current passing through the 6Ω resistor is 1.5A. Calculate the current in the 30Ω resistor

• A. 1.20A
• B. 0.90A
• C. 0.75A
• D. 0.60A

The resultant of two forces acting on an object is maximum when the angle between them is?

• A. 180°
• B. 90°
• C. 45°
• D. 0°