A bar magnet is inserted into a square wire loop (side length 5 cm) in 0.2 s, and you observe that..

A bar magnet is inserted into a square wire loop (side length 5 cm) in 0.2 s, and you observe that there is a current in the loop due to the induced voltage across the loop. You measure the induced voltage in the loop to be 2 mV. Find out the follwoing
What is the change of magnetic field, ?B, through the loop?