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.
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.
Which of the following has no effect on radiation?
nature of surface
density
surface area
temperature
Correct answer is B
Radiation depends on nature of the surface area and temperature. It is independent of density.
2.49 x 104 Nm-2
2.24 x 104 Nm-2
2.49 x 105 Nm-2
2.24 x 105 Nm-1
Correct answer is C
T = 27 + 273 = 300 K, volume, V = 10-2 m3 molar gass constant, R = 8.3 Jmol- 1k - 1 number of mole, n = 1
PV = NRT
i.e P = (NRT)/V = (1 x 8.3 x 300)/10-2
= 2.49 x 10\(^5\) Nm\(^-2\)
A vapor is said to be saturated when?
a dynamic equilibrium exists between liquid molecules and the vapour molecules
a dynamic equilibrium exists such that more molecules return to the liquid than are leaving it
the temperature of the vapour varies
the vapour pressure is atmospheric
Correct answer is A
A saturated vapour is one which is in dynamic equilibrium with its own liquid; that is as many go from the liquid to the vapour state every second return back to liquid.
The small droplet of water that forms on the grass in the early hours of the morning is
hail
dew
fog
mist
Correct answer is B
Dew point is the temperature at which the water vapour present in air is just sufficient to saturate it. Dew is formed when air is cooled below its dew point
the level of water goes up
the water in the glass outflows
the level of water remains unchanged
the level of water drops
Correct answer is D
Due to anomalous expansion of water at temperature range (0 - 4)°c, when a given mass of water turns into ice, its volume will increase, while the mass remains constant. Thus, when a given volum of ice melts, the volume of water formed will be less than the volume of ice. Hence, the level of water in the container will drop.