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प्रश्न
List two ways of increasing the strength of an electromagnet if the material of the electromagnet is fixed.
उत्तर
Two ways of increasing the strength of an electromagnet if the material of the electromagnet is fixed:
i) By increasing the amount of current flowing in the solenoid, the strength of an electromagnet can be increased.
ii) By increasing the number of turns in the solenoid, the strength of an electromagnet can be increased.
संबंधित प्रश्न
How does an electromagnet differ forma permanent magnet?
When current is 'switched on' and 'switched off' in a coil, a current is induced in another coil kept near it. What is this phenomenon known as?
In which of the following case does the electromagnetic induction occur?
The current is stopped in a wire held near a loop of wire .
In which of the following case does the electromagnetic induction occur?
A magnet is moved through a loop of wire .
The diagram 10 shows two coils X and Y. The coil X is connected to a battery S and a key K. The coil Y is connected to a galvanometer G.
When the key K is closed. State the polarity
(i)At the end of the coil X,
(ii)At the end C of the coil Y,
(iii)At the end C of the coil Y if the coil Y is (a) Moved towards the coil X, (b) Moved away from the coil X.
Draw and label the diagram of a simple D.C. motor.
(a) Explain the rotation of the coil, giving a reason for your answer.
(b) How can you reverse the direction of rotation of the armature?
(c) How can you increase the speed of rotation of the motor?
Fleming's left hand rule : electric current : : Fleming's right hand rule : _______
A current I = 10 sin(100π t) A is passed in first coil, which induces a maximum e.m.f of 5π volt in second coil. The mutual inductance between the coils is ______.
An expression for oscillating electric field in a plane electromagnetic wave is given as Ez = 300 sin(5π × 103x - 3π × 1011t)Vm-1 Then, the value of magnetic field amplitude will be ______. (Given: speed of light in Vacuum c = 3 × 108 ms-1)
