Question

Is there any possibility of induced emf due to earth's magnetism ? Explain

Answer 1

Yes.  It is possible.  When an airplane flies with its wide wings in the sky, it passes across the Earth's magnetic field.  The area under the wings is a constant.  The speed of the airplane is also a constant.  But due to variations in the  magnetic field B, there is an induced emf across the tips of the wings or the head and tail.

If the air plane is accelerating or decelerating, then there more emf induced.   The induced emf will be:

    E = - dФ/dt = - B L v

  v = speed of air plane.   L = length of air plane/ width.    B = Earth's magnetic field.   Ф = flux

The induced EMF is very small in milli volts.  We need high speeds of movement of any conductor loops to detect the  induced EMF.