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प्रश्न
A wire of length 10 cm translates in a direction making an angle of 60° with its length. The plane of motion is perpendicular to a uniform magnetic field of 1.0 T that exists in the space. Find the emf induced between the ends of the rod if the speed of translation is 20 cm s−1.
उत्तर
Given:-
Length of the rod, l = 10 cm = 0.1 m
Angle between the velocity and length of the rod, θ = 60°
Magnetic field, B = 1 T
Velocity of the rod, v = 20 cm/s = 0.2 m/s
The motional emf induced in the rod is given by
\[e = \left( \overrightarrow{v} \times \overrightarrow{B} \right) . \overrightarrow{l}\]
∴ e = Bvl sin 60°
We take the component of the length vector that is perpendicular to the velocity vector.
\[\therefore e=1 \times 0 . 2 \times 0 . 1 \times \sqrt{\frac{3}{2}}\]
= 17.32 × 10−3 V
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