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.
80.0%
76.6%
66.7%
60.7%
Correct answer is C
Efficiency = \(\frac{ma}{V.R}\) x \(\frac{100}{1}\)
V.R = number of pulleys = 6
ma = \(\frac{\text{Load}}{\text{Effort}}\) = \(\frac{200}{50}\) = 4
Efficiency = \(\frac{4}{6}\) × 100 = 66.67%
A cell of internal resistance 2 π supplies current to a 6 π resistor. The efficiency of the cell is
12.0%
25.0%
33.3%
75.0%
Correct answer is C
Internal resistance determine the maximum current that can be supplied
Efficiency = \(\frac{r}{R}\) × 100
= \(\frac{2}{6}\) × 100
= 33.3%
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