Question

 A coil is placed in a magnetic field B. Such that the direction of magnetic field is normal to the plane of the coil. The magnetic flux  linked with the coil depends on the time t as follows

             = (2t2 – 5t + 7) milli – weber

​

Answer 1

Answer:

=(5t

3

+4t

2

+2t−5) Weber

time t=2 sec

Resistance =5Ω

induced emf E=

dt

dϕ

dt

dϕ

=15t

2

+8t+2

at t=2 sec,

dt

dϕ

=15×4+8×2+2

=78 V

Also E=IR

E=78 V,R=5Ω

I=

R

k

=

5

78

=15.6 A