Examples           Answers

Faraday's Law of Induction

 

Problem 1

Given: A circular loop of wire, 9.6 cm in diameter, in a magnetic field of 1.10 T. The loop, perpendicular to the field, is removed from the field in 0.15 s.

Find:  The average induced emf

 

Problem 2

Given: A coil of wire, diameter 10.2 cm is oriented so that its plane is perpendicular to a magnetic field of 0.63 T. The magnetic field is pointing up.

In a period of 0.15 seconds, the field is changed to an orientation so that it is pointing down with a strength o 0.25 T.

Find: The average induced emf in the coil.

 

Generators

 

Problem 3

Given: A car is idling at 1100 rpm (revolutions per minute) and its generator is producing 12.4 volts

Find: The output if the rotation speed is increased to 2500 rpm. Assume nothing else changes.

  

Transformers

 

Problem 4

Given: A transformer has 164 turns in the primary coil. It is designed to change 120 V into 10,000 V.

Find: The number of turns in the secondary coil