Post Utme Physics Past Questions and Answers

Question 1256:

A gas at constant pressure of $4.0\times {10}^{5}Pa$ is cooled so that its volume decreases form $1.6m^3$ to $1.2m^3$. What work is performed by the gas?

A. $6.4\times {10}^{5}J$
B. $3.2\times {10}^{5}J$
C. $1.6\times {10}^{5}J$
D. $0.4\times {10}^{5}J$

Question 1257:

Highly polished silvery surfaces are ____________

A. Poor absorbers but good emitter of radiation
B. Good absorbers and good emitters of radiation
C. Poor emitters but good reflectors of radiation
D. Poor emitters and poor reflectors of radiation

Question 1258:

An $0.040kg$ string $0.80m$ long is stretched and vibrated in a fundamental mode with a frequency of $40Hz$. What is the speed (of propagation) of the wave and the tension in the string?

A. $64m/s$
B. $340m/s$
C. $32m/s$
D. $128m/s$

Question 1259:

What is the total power output of a source with intensity $0.050W/m^2$ at a distance of $3.0m$ from the source?

A. 112 W
B. $5.6$ W
C. 15 W
D. $30W$

Question 1260:

The superposition of two or more waves to produce a maximum or zero effect at a point is known as ____________

A. Reflection
B. Refraction
C. Diffraction
D. Interference