A 10 m wide spacecraft moves through the interstellar space at a speed 3 × 107 m s–1. A magnetic field B = 3 × 10–10 T exists in the space in a direction perpendicular to the plane of motion. Treating the spacecraft as a conductor, calculate the emf induced across its width.


Given:


Speed of spacecraft v=3× 107m/s


Magnetic field intensity B=


Width of spacecraft l=10m


We know that,


motional emf produced due to a conductor of length l moving with velocity v in a magnetic field B is given by



Since v and B are perpendicular and their cross product is parallel to l, eqn.(i) reduces to



Putting the values of v, B and l we get,




Therefore, emf induced across the width of spacecraft is 0.09V


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