PHYS 1750: SELECTED TOPICS in PHYSICS
LECTURE 34 and 35. Induction and Maxwell
22.1. | Electromotive Force and Induction | |
1. | Electromotive force: electric potential V when no current flows | |
2. | Induction: an emf induced by a changing magnetic flux | |
3. | Magnetic flux Φ = B*A*cos(θ B-A⊥) Webers | |
22.2. | Faraday's Law | |
1. | Faraday's law: V = − N*ΔΦ/Δt | |
2. | Lenz's law: current opposes change in Φ | |
22.3. | Motion leads to voltage | |
1. | V = B*l*v | |
2. | Applications: railguns, tape recorders | |
23.1. | Maxwell's Equations | |
1. | ∑ ΔA*E⊥ = Q / εo; sum over surface elements of a volume | |
2. | ∑ ΔA*B⊥ = 0; sum over surface elements of a volume | |
3. | ∑ Δl*E|| = - ΔΦB / Δt; sum over line elements of a loop | |
4. | ∑ Δl*B|| = μoεo ΔΦE / Δt + μoI: sum over line elements of a loop |