Electromagnetic...

A transformer has 100 turns in the primary coil and carries 8 A current. If input power is one kilowatt, the number of turns required in the secondary coil to have 500 V output will be

An ideal transformer has 500 and 5000 turn in primary and secondary windings respectively. If the primary voltage is connected to a 6 V battery then the secondary voltage is

In a primary coil 5 A current is flowing on 220 volts. In the secondary coil 2200 V voltage produces. Then ratio of number of turns in secondary coil and primary coil will be

A step-down transformer is used on a 1000 V line to deliver 20 A at 120 V at the secondary coil. If the efficiency of the transformer is 80% the current drawn from the line is

The output voltage of a transformer connected to 220 volt line is 1100 volt at 2 A current. Its efficiency is 100%. The current coming from the line is

Quantity that remains unchanged in a transformer is

In a region of uniform magnetic induction B =10^–2 tesla, a circular coil of radius 30 cm and resistance π² ohm is rotated about an axis which is perpendicular to the direction of B and which forms a diameter of the coil. If the coil rotates at 200 rpm the amplitude of the alternating current induced in the coil is

The number of turns of the primary and the secondary coils of a transformer are 10 and 100 respectively. The primary voltage and the current are given as 2 V and 1 A. Assuming the efficiency of the transformer as 90%, the secondary voltage and the current respectively are

In an ideal transformer the number of turns of primary and secondary coil is given as 100 and 300 respectively. If the power input is 60 W, the power output is

A copper rod of length l is rotated about one end perpendicular to the magnetic field B with constant angular velocity ω. The induced e.m.f. between the two ends is