A rectangular loop of length \( 2.5 \, \text{m} \) and width \( 2 \, \text{m} \) is placed at \( 60^\circ \) to a magnetic field of \( 4 \, \text{T} \). The loop is removed from the field in \( 10 \, \text{s} \). The average emf induced in the loop during this time is :
