Post Utme Physics Past Questions and Answers

Question 61:

Which of the following quantities of water has undergone the greatest change from its heat content at melting point?

A. $0.5\mathrm{kg}$ of water at $3^{\circ }\mathrm{C}$
B. $0.2\mathrm{kg}$ of water at $8^{\circ }\mathrm{C}$
C. $0.005\mathrm{kg}$ of water at ${80}^{\circ }\mathrm{C}$
D. $0.1\mathrm{kg}$ of water at ${12}^{\circ }\mathrm{C}$

Question 62:

Which would cause a more serious burn: $30\mathrm{g}$ of steam or $30\mathrm{g}$ of liquid water, both at ${100}^{\circ }\mathrm{C}$; and why is this so?

A. Water, because it is denser than steam.
B. Steam, because of its specific heat capacity.
C. Steam, because of its latent heat of vaporization.
D. Water, because its specific heat is greater than that of steam.

Question 63:

A certain radioactive element has a half life of 20 years. How long will it take the activity to become $1/4$ of its original?

A. 20 years
B. 40 years
C. 60 years
D. 80 years

Question 64:

A plane progressive wave is represented by $y2\sin 100t0.2x$ where all the symbols have their usual meanings. What is the velocity of the wave?

A. $500\mathrm{m}{\mathrm{s}}^{-1}$
B. $400\mathrm{m}{\mathrm{s}}^{-1}$
C. $200\mathrm{m}{\mathrm{s}}^{-1}$
D. $100\mathrm{m}{\mathrm{s}}^{-1}$

Question 65:

A point on a stationary wave where there is no movement of the medium is called ____________

A. Node
B. Antinode
C. Note
D. Amplitude