Electromagnetic induction
Answers are for parents and teachers.
1
N = 100, ΔΦ = 20 mWb, Δt = 0.05 s. What is |Eᵢ| in V?
40
2
|Eᵢ| = 12 V, Δt = 0.5 s, N = 60. What is ΔΦ in mWb?
100
3
A loop of resistance 3 Ω has an EMF of 0.6 V. What is the current in mA?
200
4
Why does the galvanometer pointer deflect the other way when the magnet is pulled out?
The flux now decreases, so by Lenz's rule the induced current reverses.
5
Why does the number of turns affect the EMF as well as the rate of flux change?
Each turn produces its own EMF and they add in series: E = N·ΔΦ/Δt.