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.
7.53 x 105 Jkg\(^{-1}\)
7.53 x 10-2Jkg\(^{-1}\)
\(7.53 \times 10^{4}\)Jkg\(^{-1}\)
7.53 x 10-3Jkg\(^{-1}\)
Correct answer is C
Quantity of heat = mass(m) × specific latent heat (L)
Q = mL
L = \(\frac{Q}{m}\)
= \(\frac{1.13 \times 10^{6}}{15}\)
= \(7.53 \times 10^{4}\)Jkg\(^{-1}\)
Under which of the following conditions is workdone
A man supports a heavy food above his head with his hands
A boy climbs onto a table
A man pushes unto a table
A woman holds a pot of water
Correct answer is B
For work to be done, distance must be involved because
workdone = force × distance
Under what conditions are cathode rays produced in a discharge tube?
High pressure and low voltage
High pressure and high voltage
Low pressure and low voltage
Low pressure and high volatge
Correct answer is D
Cathode rays are produced in a discharge tube under Low pressure and high voltage
0.8N
2.5N
0.5N
1.0N
Correct answer is C
Upthrust = change in weight
density = \(\frac{\text{mass}}{\text{volume}}\)
Mass of liquid displaced = Density of Liquid × Volume;
= \(10^{3} \times 50 \times 10^{−6}m^{3}\)
= 0.05kg
(Note that the volume of \(50cm^{3}\) was converted to \(m^{3}\) by multiplying by \(10^{6}\)) i.e \(50cm^{3} = 50 \times 10^{−6}m^{3}\)
Since mass displaced = 0.05kg
Upthrust = mg = 0.05 × 10
= 0.5N
Why do soldiers march disorderly while crossing a bridge?
To prevent resonance on the bridge
To set the bridge into resonance
To make the b ridge collapse
To spread their weight evenly on the bridge
Correct answer is A
Soldiers march disorderly while crossing a bridge to prevent resonance because when soldiers march in orderly manner across a bridge, they generate a rhythmic oscillation of wave on the bridge and at a certain point, would start oscillation to the same rhythm as that of the marching steps. This oscillation would reach a maximum peak when the bridge can no longer sustain its own strength and hence collapses. So for this reasons, soldier are ordered to march disorderly while crossing a bridge.