Post Utme Physics Past Questions and Answers

Question 571:

A converging, lens of 15cm focal length forms an image of an object placed \(9 \mathrm{~cm}\) from it. What is its position and magnification?

A. \(6 \mathrm{~cm}\) and \(3 / 2\)
B. \(6 \mathrm{~cm}\) and \(1 / 3\)
C. \(6 \mathrm{~cm}\) and \(-2 / 3\)
D. \(6 \mathrm{~cm}\) and \(2 / 3\)

Question 572:

A gramophone record takes \(5 s\) to reach its constant angular velocity of \(4 \pi \mathrm{rads}^{-1}\) from rest. Find it constant angular acceleration.

A. 0. \(4 \pi \mathrm{rrads}^{-2}\)
B. \(0.87\) nrads \(^{-2}\)
C. \(1.3 \pi \mathrm{rrads}^{-2}\)
D. \(2.04\) nrads \({ }^{-2}\)

Question 573:

A machine has a velocity ratio of 4 . If it requires \(800 \mathrm{~N}\) to overcome a load of \(1600 \mathrm{~N}\), what is the efficiency of the machine?

A. \(60 \%\)
B. \(50 \%\)
C. \(40 \%\)
D. \(2 \%\)

Question 574:

A piece of iron weighs \(250 \mathrm{~N}\) in a liquid of density \(100 \mathrm{kgm}^{-3}\). The volume of the iron is ____________

A. \(5.0 \times 10^{-3} \mathrm{~m}^{3}\)
B. \(4.5 \times 10^{-3} \mathrm{~m}^{3}\)
C. \(2.5 \times 10^{-3} \mathrm{~m}^{3}\)
D. \(2.0 \times 10^{-3} \mathrm{~m}^{3}\)

Question 575:

A ray of light is incident on an equilateral triangular glass prism of retractive index 3/2. Calculate the angle through which ray is minimally deviated in the prism.

A. \(37.1^{\circ}\)
B. \(48.6^{\circ}\)
C. \(30.0^{\circ}\)
D. \(42.0^{\circ}\)