⚡ Foundations — Flux in Motion

Drag the apparatus (or use the sliders). Watch the flux Φ through the circuit change, and see the induced emf respond — exactly as Faraday’s and Lenz’s laws predict.

Every tab here is the same underlying law: emf = −N·dΦ/dt. What differs each time is WHICH factor in Φ = N·B·A·cosθ is doing the changing — B, A, θ, or N itself.

What is this?

Apparatus — drag the highlighted parts

Flux Φ through the circuit — is it changing?

Induced EMF — Lenz's law in action

Which way does the current actually flow?

Live calculation