The core of a transformer is usually laminated in order to
reduce magnetic leakage
reduce eddy current
prevent vibration of the transformer
make magnetic reversal in the core much easier
Correct answer is B
No explanation has been provided for this answer.
The magnetic relay is a device used for
timing in sports
storing magnetic field
reading the magnitude of magnetic flux
controlling another circuit carrying larger current
Correct answer is D
No explanation has been provided for this answer.
A 12\(\Omega\) resistor dissipates 8kJ of heat in 20s. Calculate the current through the resistor
5.8A
6.9A
30.0A
33.3A
Correct answer is A
Q = I2Rt
I = \(\sqrt{\frac{Q}{Rt}}\)
= \(\sqrt{\frac{8000}{12 \times 20}}\)
= 5.8
P
Q
R
S
Correct answer is B
The determinant of the brightness of a bulb is the power (watts) of the circuit.
Recall that Power (P) = \(\frac{V^2}{R}\).
Since the resistance is to be used as a divisor, it means the smaller the resistance, the greater the power.
0.63A
0.50A
0.31A
0.22A
Correct answer is A
I = \(\frac{f}{n} = \frac{1}{6 - 2}\)
I = \(\frac{v}{R + r} = \frac{2}{3} + \frac{1}{6} = 0.63\)A
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