Electromagnetic Induction - Result Question 1

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1. A 800 turn coil of effective area $0.05 m^{2}$ is kept perpendicular to a magnetic field $510^{-5}$ $T$. When the plane of the coil is rotated by $90^{\circ}$ around any of its coplanar axis in $0.1 s$, the emf induced in the coil will be :

======= ####1. A 800 turn coil of effective area $0.05 m^{2}$ is kept perpendicular to a magnetic field $510^{-5}$ $T$. When the plane of the coil is rotated by $90^{\circ}$ around any of its coplanar axis in $0.1 s$, the emf induced in the coil will be :

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/electromagnetic-induction/electromagnetic-induction—result-question-1.md (a) $2 V$

(b) $0.2 V$

(c) $2 \times 10^{-3} V$

(d) $0.02 V$

[2019]

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Solution:

  1. (d) Given :

Magnetic field $B=5 \times 10^{-5} T$

Number of turns in coil $N=800$

Area of coil A $=0.05 m^{2}$

Time taken to rotate $=\Delta t=0.1 s$

Initial angle $\theta_1=0^{\circ}$

Final angle $\theta_2=90^{\circ}$

Change in magnetic flux $\Delta \phi$

$=NBA \cos 90^{\circ}-BA \cos 0^{\circ}$

$=-NBA$

$=-800 \times 5 \times 10^{-5} \times 0.05$

$=-2 \times 10^{-2}$ weber

$ \theta=-\frac{\Delta \phi}{\Delta t}=\frac{-(-) 2 \times 10^{-3} Wb}{0.1 s}=0.02 V $