A circuit in which there is a current of 5 amp is changed so that the current falls to zero in 0.1s. If an average e.m.f of 200 volts is induced, what is the self-inductance of the circuit?
Correct answer: A. 4 henrys
- A. 4 henrys
- B. 8 henrys
- C. 12 henrys
- D. 16 henrys
- E. 20 henrys
Explanation
Initial currect= I1 = 5.0 A Final current= I2= 0 A change in current , dI= I1 -I2 =5A Time taken for the change= 0.1s Avg emf= 200V e=L di/dt L= e /di/dt 200/5/01 = 4H Hence the self inductance of the coil is 4H.
Last updated
About Electromagnetism
Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
Practise Electromagnetism
1,176 free Electromagnetism MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
1 Tesla is equal to:
1 tesla is equal to:
2.5π µF capacitor and 3000-ohm resistance are joined in series to an AC source of 200 volts and frequency. The power factor of the circuit and the power dissipated in it will respectively be:
A 10 cm long solenoid has 100 turns. What will be the magnetic field inside it along its axis if one-microampere current is passed through it?
A 100-turn coil of area 0.1 m2 rotates at half a revolution per second. It is placed in a uniform magnetic field of 0.01 T perpendicular to the axis of rotation of the coil. Calculate the maximum voltage generated in the coil?