Question

A 0.400 mm diameter copper wire makes up a 136 turns, 6.70 cm diameter coil. There is a magnetic field parallel to the axis of the coil. If the induced current in the coil is 4.80 A, what is the rate of change of the magnetic field? what formula do i use for this?

Answer 1

faradays law

\(\mathcal{E} = - N \dot \Phi \) which here \(= - N \dot B A\) as A is constant. N is number of turns

looks like you will also need to work out the resistance of the copper coil using the resistivity idea/ formula \(R = \dfrac{\rho l }{A}\)