2.20 × 10\(^3\)m
5.0 × 10\(^2\)m
5.0 × 10\(^5\)m
11.8 × 10\(^{11}\)m
Correct answer is B
V = fλ
λ = \(\frac{v}{f}\)
= \(\frac{3 \times 10^8}{600 \times 10^3}\) = 500m
= 5 × 102m
N.B 600KHz Frequency = 600 × 103Hz
100w
200w
400w
500w
Correct answer is D
Power is the time rate of doing work
i.e power = \(\frac{\text{energy}}{\text{time}}\)
Since energy = mgH
∴ power = \(\frac{mgH}{t}\)
= \(\frac{50 \times 10 \times 5}{t}\)
= 500W
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
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