induction 7-2

A circular coil is placed near a straight conductor as shown below. When the current in the straight conductor increases, the current in the coil is

• clockwise

• anticlockwise

• normal to the plane oi coil

• None of them.

The electric current in a circuit varies from + 2A to – 2A in a time 10^-2 s. Another coil of resistance 20 Ω and inductance 2H is placed here it. What will be the induced current in the second coil?

• 4A

• 8A

• 20A

• 40A

When the current through a solenoid increases at a constant rate, the induced current:

• is a constant and is in the direction of inducing current

• is a constant and is opposite to the direction of the inducing current.

• increases with time and is in the direction of the inducing current.

• increases with time and is opposite to the direction of the inducing current

Which of the following is/are equal to Henry?

• Volt second/ampere

• Volt(second)²/coulomb

• Joule (second)²/(coulomb)²
  

• All of these

A coil of metal wire is kept stationary in a non-uniform magnetic field:

• An e.m.f. and current both are induced in the coil.

• An e.m.f. but not the current is induced iii the coil.

• Current but not the e.m.f is induced in the coil.

• Neither e.m.f. nor current is induced in the coil.

Induced e.m.f. produced in a coil rotating in a magnetic field will be maximum when the angle between the axis of coil and direction of magnetic field is:

• 90°

• 45°

• 0°

• 180°

Induced e.m.f. produced in a coil rotating in a magnetic field will be maximum when the angle between the axis of coil and direction of magnetic field is:

• 90°

• 45°

• 0°

• 180⁰

A coil having 500 square loops each of side 10 cm is placed normal to the magnetic field which increases at a rate of 1.0 Wb s^-1. The induced e.m.f. is;

• 0.1V

• 5 V

• 0.5 V

• 1.0 V

If a core of soft iron is introduced into a coil its coefficient of self induction gets ………………

• increased

• decreased

• moderate

• <1

When the rate of change of current through a closed circuit is unity, then the induced e.m.f. produced in it is equal to ………………

• self inductance L

• Mutual inductance M

• both

• none