A toroidal solenoid has 590 turns, cross-sectional area 6.20 cm^2 , and mean radius 5.00 cm .Part A. Calcualte the coil's self-inductance. Part B. If the current decreases uniformly from 5.00 A to 2.00 A in 3.00 ms, calculate the self-induced emf in the coil. Part C. The current is directed from terminal a of the coil to terminal b. Is the direction of the induced emf froma to b or from b to a?

Complete Question

A toroidal solenoid has 590 turns, cross-sectional area 6.20 cm^2 , and mean radius 5.00 cm .

Part A. Calculate  the coil's self-inductance.

Part B. If the current decreases uniformly from 5.00 A to 2.00 A in 3.00 ms, calculate the self-induced emf in the coil.

Part C. The current is directed from terminal a of the coil to terminal b. Is the direction of the induced emf from a to b or from b to a?

Part A  

Part B  

Part C

    From terminal a to terminal b

Explanation:

From the question we are told that

      The  number of turns is  

      The cross-sectional area is  

      The  radius is

Generally the coils self -inductance is mathematically represented as

Where is the permeability of  free space with value

substituting values

Considering the Part B

      Initial current is

      Current at time t is

       The  time taken is  

The self-induced emf is mathematically evaluated as

=>        

substituting values

The direction of the induced emf is  from a to b because according to Lenz's law the induced emf moves in the same direction as the current

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge