Question

a coil having an area 10 cm and turn 1000 is kept in a magnetic field of intensity .1 tesla, the plane of coil is perpendicular to the magnetic field if the coil is turned through 180 in .2 second then find induced emf in it also find the induced current in it if its resistance is 10 ohm

Answer 1

Correct option is

C

40mV

Area of the coil  A=500 cm  

2

=0.05 m  

2

 

Number of coil  N=1000

Magnetic field  B=4×10  

−5

 Wb/m  

2

 

Magnetic flux passing through the coil initially  (θ=0  

o

),    

ϕ  

i

​

=NBAcosϕ=1000×4×10  

−5

×0.05×cos0  

o

=0.002 Wb

Magnetic flux passing through the coil finally  (θ=180  

o

),    

ϕ  

f

​

=NBAcosϕ=1000×4×10  

−5

×0.05×cos180  

o

=−0.002 Wb

Thus change of flux  Δϕ=ϕ  

i

​

−ϕ  

f

​

=0.002−(−0.002)=0.004 Wb

Change in time  Δt=0.1 s

Thus average emf induced  E=  

Δt

Δϕ

​

=  

0.1

0.004  

=40

I HOPE IT HELP FULL TO YOU