Advertisements
Advertisements
Question
How does a magnetic field set up by a solenoid change when strength of current in the solenoid is decreased?
Advertisements
Solution
By decreasing the current flowing in the solenoid, the intensity of magnetic field decreases.
RELATED QUESTIONS
Suppose you are given a long bar magnet and you are asked to break it into four small magnets. Draw diagrams showing the polarities of each broken part.
Complete the following sentence :
On reserving the direction of current in a wire, the magnetic field produced by it gets _____.
State two factors on which the magnitude of an induced e.m.f. in the secondary coils of a transformer depends.
The magnetic flux through a coil having 100 turns decreases from 5 milli weber to zero in 5 second. Calculate the e.m.f. induced in the coil.
A straight wire is held vertical and current is passed in it in the upward direction. A compass needle is kept near the wire in north of it. How is the needle deflected? What is the change in the deflection of the needle if the current in wire is reversed?
State three factors which govern the speed of rotation of an electric motor.
The primary windings of a step-up transformer are usually made of thicker wire than the secondary. Explain.
State important properties (or characteristics) of magnetic lines of force around a straight conductor.
Point out three differences between an electromagnet and a bar (or permanent) magnet.
State and explain Maxwell’s Cork Screw Rule.
