A circular coil consists of 70 closely wound | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) Given: Number of turns $N = 70$,radius $r = 10 \,cm = 0.1 \,m$,magnetic field $B = 2 	imes 10^{-3} \,T$,current $I = 2.2 \,A$.Since the magnetic

Vedclass · Accepted Answer

$2$

Vedclass · Answer

(A) Given: Number of turns $N = 70$,radius $r = 10 \,cm = 0.1 \,m$,magnetic field $B = 2 	imes 10^{-3} \,T$,current $I = 2.2 \,A$.Since the magnetic field is perpendicular to the plane of the coil,the angle between the area vector and the magnetic field is $	heta = 0^{\circ}$.The magnetic flux linked with the coil is $\phi = N B A \cos 	heta$.Substituting the values: $\phi = 70 	imes (2 	imes 10^{-3}) 	imes (\pi 	imes (0.1)^2) 	imes \cos 0^{\circ}$.$\phi = 140 	imes 10^{-3} 	imes \pi 	imes 0.01 = 1.4 \pi 	imes 10^{-3} \,Wb$.Using $\pi \approx 3.14$,$\phi = 1.4 	imes 3.14 	imes 10^{-3} \approx 4.4 	imes 10^{-3} \,Wb$.For the net flux to vanish,the flux due to the current in the coil must equal the external flux: $\phi = L I$.$L = \frac{\phi}{I} = \frac{4.4 	imes 10^{-3}}{2.2} = 2 	imes 10^{-3} \,H = 2 \,mH$.

Similar Questions

When the current in a coil changes from $8 \; A$ to $2 \; A$ in $3 \times 10^{-2} \; s$,the $e.m.f.$ induced in the coil is $2 \; V$. The self-inductance of the coil (in $mH$) is:

When the current through an inductor is changed from $2 \,A$ to $6 \,A$ in time $2 \,s$, the emf induced in it is $3 \,V$. Then the inductance of the inductor is (in $\,H$)

The self-inductance of a long solenoid of cross-sectional area $A$,length $l$ and $n$ turns per unit length is given by

Two identical inductors carry currents that vary with time according to linear laws (as shown in the figure). In which of the two inductors is the self-induced $emf$ greater?

The current passing through a choke coil of $5 \, H$ is decreasing at the rate of $2 \, A/s$. The $e.m.f.$ developed across the coil is ....... $V$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module