Physics Past Questions and Answers

An electron makes a transition from a certain energy level E_k to the ground state E₀. If the frequency of emission is 8.0 x 10¹⁴Hz The energy emitted is

A 8.25 x 10^-19J
B 5.28 x 10^-19J
C 5.28 x 10¹⁹J
D 8.25 x 10¹⁹J

Question 47:

A force of 100N was used to kick a football of mass 0.8kg. Find the velocity with which the ball moves if it takes 0.8s to be kicked

A \(32ms^{-1} \)
B \(50ms^{-1} \)
C \(64ms^{-1} \)
D \(100ms^{-1} \)

Question 48:

Given that young's modulus for aluminium is 7.0 x 10¹⁰Nm^-2 and density is 2.7 x 10³kgm^-3 find the speed of the sound produced if a solid bar is struck at one end with a hammer

A 5.1 x 10³ms^-1
B 4.2 x 10³ms^-1
C 3.6 x 10³ms^-1
D 2.8 x 10³ms^-1

Question 49:

If the uncertainty in the measurement of the position of a particle is 5.0 x 10^-10m, the uncertainty in the momentum of the particle is

A 1.32 x 10^-44Ns
B 3.30 x 10^-44Ns
C 1.32 x 10^-24Ns
D 3.30 x 10^-24Ns