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 $5s$ 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. $60\mathrm{\%}$
B. $50\mathrm{\%}$
C. $40\mathrm{\%}$
D. $2\mathrm{\%}$

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. ${42.0}^{\circ }$