An electron moves on a straight line path XY as shown. The abcd is a coil adjacent to the path of electron. What will be the direction of current, if any, induced in the coil? […]
A conducting square frame of side ‘a’ and a long straight wire carrying current I are located in the same plane as shown in the figure. The frame moves to the right with a constant […]
A thin semicircular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B, as shown in the figure. The potential difference developed across the ring when its […]
A transformer rated at 10 kW is used to connect a 5 kV transmission line to a 240 V circuit. The ratio of turns in the windings of a transformer
Options
(a) 5 (b) […]
If the self inductance of 500 turn coil is 125 mH, then the self inductance of similar coil of 800 turns is
Options
(a) 48.4 mH (b) 200 mH (c) 187.5 mH (d) 320 […]
The flux linked with a circuit is given by φ=t³+3t-7. The graph between time (x-axis) and induced emf (y-axis) will be a
Options
(a) straight line with negative intercept (b) straight line with […]
Two coaxial solenoids are made by winding thin insulated wire over a pipe of cross-sectional area A=10 cm² and length =20 cm. If one of the solenoids has 300 turns and the other 400 turns, […]
Which wavelengths of sun is used finally as electric energy?
Options
(a) Radio waves (b) Infra red waves (c) Visible light (d) Micro waves
Correct Answer:
Infra red waves
Explanation:
Infrared rays or heat […]
The turn ratio of a transformer is 1:2. An electrolytic dc cell of emf 2 volt is connected to its primary. The output voltage is
Options
(a) 2 V (b) 0 V (c) […]
A transistor-oscillator using a resonant circuit with an inductor L (of negligible resisitance) and a capacitor C in series produce oscillations of frequency f. If L is doubled and C is changed to 4C, the […]
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