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12) A rod PQ of length 2 is rotating about one end P in a uniform magnetic field B which is perpendicular to the plane of rotation of the rod . Point M is the mid point of the rod. Find the induced between M & Q if that between P & Q = 100V.

in the given question, the emf for full length is given, i.e 100V and we have to calculate the emf for half of the length. just, in the above formula put L as (L/2). which when squared gives one-fourth(1/4) of induced emf.

So, the induced emf for half length is 1/4 of induced emf as that for full length.

So, the answer 25V.

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