If the self inductance of 500 turn coil is 125 mH, then the self inductance
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 […]
Physics
The flux linked with a circuit is given by φ=t³+3t-7. The graph between time
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
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?
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
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
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 […]
The core of a transformer is laminated because
The core of a transformer is laminated because
Options
(a) ratio of voltage in primary and secondary may be increased (b) energy losses due to eddy currents may be minimised (c) the weight […]
The current through an inductor changes from 3 A to 2 A is 1 m/s. If induced e.m.f.
The current through an inductor changes from 3 A to 2 A is 1 m/s. If induced e.m.f. in inductor is 5V then L is
Options
(a) 5×10⁻² H (b) 5×10⁻³ H (c) 2.5×10⁻³ […]
Which of the following is the function of the step-up transformer?
Which of the following is the function of the step-up transformer?
Options
(a) Low voltage, high current to high voltage and low current (b) Low voltage, low current to high voltage and high […]
In an inductor when current changes from 2 A to 18 A in 0.05 sec, the e.m.f. induced
In an inductor when current changes from 2 A to 18 A in 0.05 sec, the e.m.f. induced is 20 V. The inductance L is
Options
(a) 62.5 mH (b) 625 mH (c) 6.25 […]