A circular loop of flexible iron wire has an initial circumference of 162cm , bu

Question

A circular loop of flexible iron wire has an initial circumference of 162cm , but its circumference is decreasing at a constant rate of 13.0 cm/s due to a tangential pull on the wire. The loop is in a constant uniform magnetic field of magnitude 0.800 T, which is oriented perpendicular to the plane of the loop. Assume that you are facing the loop and that the magnetic field points into the loop.

Part A Find the magnitude of the emf induced in the loop after exactly time 5.00s has passed since the circumference of the loop started to decrease

emf_____V

Explanation / Answer

Radius Initially = 162 / 2 x 3.14 = 25.79 cm/s

rate of decrease of radius = 13 / 2 x 3.14 = 2.07 cm/s = dr/dt

E = d/dt

= B x dA/dt

A = r2

dA/dt = 2 r (dr/dt)

r at five seconds = 25.79 - 5 x 2.07 = 15.44

E = 0.8 x 2 x 3.14 x (15.44 x 10-2) x (2.07 x 10-2) = 0.016 V

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.