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.

1,871.

The eclipse of the moon occurs when the

A.

moon comes exactly between the earth and the sun

B.

earth comes exactly between the moon and the sun

C.

sun comes exactly between the earth and the moon

D.

moon reflects all the rays from the sun onto the earth

Correct answer is B

No explanation has been provided for this answer.

1,872.

A note of frequency 2000Hz has a velocity of 400 ms-1. calculate the wavelength of the note

A.

5.0m

B.

2.0m

C.

0.5m

D.

0.2m

Correct answer is D

\(\pi = \frac{v}{f} = \frac{400}{2000} = 0.2m\)

1,873.

The S.I units of frequency, period and amplitude of a wave are respectively

A.

hertz, second and centimeter

B.

second, metre and hertz

C.

metre, hertz and seconds

D.

hertz, second and metre

Correct answer is D

No explanation has been provided for this answer.

1,874.

The temperature of a liquid falls after some of it has evaporated because

A.

the liquid left is smaller in volume and the breeze easily cools it

B.

the more energetic molecules have escaped into the atmosphere

C.

the liquid left has less latent heat

D.

after evaporation impurities are left behind

Correct answer is B

No explanation has been provided for this answer.

1,875.

A quantity of steam at 100°C condenses to water at the same temperature by releasing 6.9 x 104J of energy. Calculate the mass of the condensed steam. [specific latent heat of vaporization of water = 2.3 x 106 J kg-1]

A.

3.0 x 10-1 kg

B.

3.0 x 10-2 kg

C.

3.0 x 10-3 kg

D.

3.0 x 10-4 kg

Correct answer is B

M = \(\frac{Q}{T} = \frac{6.9 \times 10^{4}}{2.3 \times 10^6} = 3 \times 10^{-2} kg\)