Physics questions and answers

Physics Questions and Answers

If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.

4,091.

The diagram above shows a solid figure with base PQ and center of gravity G on a inclined plane. Which of the following statements is correct

A.

The solid will fall over if the vertical line through G lies outside the base

B.

The solid will fall over if the vertical line through lies inside the base

C.

The solid will not fall over if the vertical line through G lies outside the base

D.

The solid can never fall over

Correct answer is A

The solid will fall over if when the vertical line through G lies outside the base, when slightly tilted

4,092.

The figure above represents a frictionless pulley system in which a weight W is in equilibrium with a weight of 40N. Find the value of W

A.

13.3N

B.

20.0N

C.

40.0N

D.

80.0N

Correct answer is D

With P1 and P2 as shown (make a V.R of 2), the weight W = 40N * 2 = 80N

4,093.

The diagram above shows the velocity-time graph of a vehicle. Its acceleration and retardation respectively are

A.

8.0 ms-2, 4,0 ms-2

B.

4.0 ms-2, 8.0 ms-2

C.

4.0 ms-2, 2.0 ms-2

D.

2.0 ms-2, 4.0 ms-2

Correct answer is C

Acceleration = slope = AE/OE = 80/20 = 4m/s2
∴ acceleration and retardation = 4m/s2; 2m/s2

4,094.

Vibration in a stretched spring cannot be polarized because they are

A.

stationary waves

B.

transverse waves

C.

longitudinal waves

D.

mechanical waves

Correct answer is C

In longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization.

4,095.

the pressure of 3 moles of an ideal gas at a temperature of 27°C having a volume of 10-3m3 is

A.

2.49 x 105-2

B.

7.47 x 105-2

C.

2.49 x 106-2

D.

7.47 x 106-2

Correct answer is D

From the relation PV = nRT
V = 10-33; n = 3 moles; T = 27 + 273 = 300k
R = 8.3 j mol-1 K-1
=> P = nRT/V = 3 X 8.3 X 300/10-3 = 7.47 X 106 Nm-2