PhysicsRankPREVIEWTry a problem

THE PRACTICE STUDIO

Go slowly. Ask why. Make it yours.

PRACTICE · MEMBERSIntermediate · Single correct

PRACTICE / Lenz law

The induced field opposes the change

A single-turn loop of area 0.040 m² lies in the page and has resistance 2.0 Ω. A uniform field into the page increases at 3.0 T/s.

What is the signed current if counterclockwise is positive as seen by you?

Organize the givens & assumptions
  • Area = 0.040 m²
  • Resistance = 2.0 Ω
  • Into-page field increases at 3.0 T/s

Stationary loop, negligible self-inductance and uniform applied field normal to its plane; positive area normal is out of the page by the counterclockwise convention.

  1. A+0.060 A+0.060\ \mathrm A
  2. B−0.060 A-0.060\ \mathrm A
  3. C+0.120 A+0.120\ \mathrm A
  4. D0 A0\ \mathrm A

Try it on paper first. Free sample problems in every collection include the complete reasoning: find one in this collection →