A square-shaped coil of area \(70 \, \text{cm}^2\) having 600 turns rotates in a magnetic field of \(0.4 \, \text{wbm}^{-2}\), about an axis which is parallel to one of the sides of the coil and perpendicular to the direction of the field. If the coil completes 500 revolutions in a minute, the instantaneous emf when the plane of the coil is inclined at \(60^\circ\) with the field, will be ________ V. (Take \(\pi = \frac{22}{7}\))