Electromagnets-need help!!

Question

this is me being totally confused by my homework..can anyone with a little more knowledge please help!

A circular coil of wire has radius 0.24 m, with 882 turns of wire in the coil. It is located in a magnetic field of 1.25 T, directed perpendicular to the plane of the loop.

(a) What is the magnetic flux through the loop (in T m2)?

(b) Now suppose the coil is attached to a 110 ohm resistor, and the magnetic field decreases to 0 in 1 second. What is the induced current in the circuit?

Answer 1

The area of the coil is:

A = πr² = π x (0.24 m)² = 0.181 m²

The magnetic flux is:

Φ = BA = 1.25 T x 0.181 m² = 0.226 Tm²

The units should actually be Webers (Wb) because they are SI. Whoever told you to use Tesla-meters squared should be using SI.

The induced emf is:

Ɛ = - N∆Φ / ∆t

= (- 882 turns x - 1.25 T) / 1.00 s

= 1100 V

The induced current is:

I = Ɛ / R

= 1100 V / 110 Ω

= 10 A