Use the following figure for the next problem.
-A rectangle is bent on two sides at 90 $\circ$ so that one end lies along the xy-plane while the other end lies along the xz-plane.The length a = 10 cm and b = 30 cm.At t = 0,a magnetic field of strength B = 0.1 T lies in the yz-plane and points at an angle $\theta$ = 30 $\circ$ and 10 ms later the field points in the opposite direction.The EMF induced in the rectangle is
A)10.4 V
B)6.0 V
C)12 V
D)8.2 V
E)None of these is correct.

Question

Use the following figure for the next problem. 
-A rectangle is bent on two sides at 90 $\circ$ so that one end lies along the xy-plane while the other end lies along the xz-plane.The length a = 10 cm and b = 30 cm.At t = 0,a magnetic field of strength B = 0.1 T lies in the yz-plane and points at an angle $\theta$ = 30 $\circ$ and 10 ms later the field points in the opposite direction.The EMF induced in the rectangle is
A)10.4 V 
B)6.0 V 
C)12 V 
D)8.2 V 
E)None of these is correct.

Quizplus · Accepted Answer

The EMF induced in a rectangular loop rotating in a magnetic field is given by:
EMF = B * l * w * sin(θ)
where B is the strength of the magnetic field, l and w are the dimensions of the rectangle, and θ is the angle between the magnetic field and the normal to the plane of the rectangle.
In this case, B = 0.1 T and θ = 30°.
At t = 0, the loop is perpendicular to the magnetic field, so the EMF induced is zero.
At t = 10 ms, the loop has rotated by an angle of 30°, so the EMF induced is:
EMF = 0.1 * 10 * 30 * sin(30°) = 8.2 V
Therefore, the best choice is D.

Use the Following Figure for the Next Problem ∘\circ∘ So That One End Lies Along the Xy-Plane While

Use the Following Figure for the Next Problem $\circ$ So That One End Lies Along the Xy-Plane While