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.
The instrument used to measure the pressure of a gas is
barometer
thermometer
hydrometer
manometer
Correct answer is D
Barometer is used to measure atmosphere pressure
Thermometer is used to measure temperature
Hydrometer is used to measure relative density of a liquid
Manometer is used to measure the pressure of a gas
The net capacitance in the circuit above is
80µF
6.0µF
4.0µF
2.0µF
Correct answer is D
For capacitance i n parallel, 2µF and 2µF are in parallel,
their equivalence is 2µF and 2µF = 4µF
The 4µF generated is now in series with the remaining 4µF.
The net capacitance for series connection is
\(\frac{1}{C}\) = \(\frac{1}{4}\) + \(\frac{1}{4}\) = 1 + \(\frac{1}{4}\) = \(\frac{2}{4}\)
C = \(\frac{4}{2}\)
= 2µF
number of turns in the coil is increased
strength of the field magnet is increased
slip rings are replaced with split ring commutator
coil is wound on a soft iron armature
Correct answer is C
A d.c generator is one in which its current is allowed to flow in one direction even through it may vary in value an a.c generator can only be made to produce a d.c by replacing the two slip rings with a single split ring or commutator
240v
340v
480v
57600v
Correct answer is B
The relationship between the peak value and r.m.s value of electricity supply is given as
V\(_{r.m.s}\) = \(\frac{V_o}{\sqrt{2}}\)
where Vo = peak voltage
∴ Vo = V\(_{r.m.s}\) × √2
= 240 × √2
= 339.5v
= 340v
1:4
4:1
1:1
2:1
Correct answer is C
H = mcθ
HP = HQ, θP = 2θ,
mP = \(\frac{1}{2}\)mQ
∴ HP = mQCPθP, also HQ = mQCQθQ
Since HP = HQ
∴ mPcPθP = mQcPθq
Putting in the conditions
\(\frac{1}{2}\)mQ × cP × 2θQ = mQ × θQ × cQ
∴ cP = cQ
\(\frac{C_p}{C_Q}\)= \(\frac{1}{1}\)
= 1:1