The voltage induced by inductors can be represented by the following equation: = L I / t 1.

The voltage induced by inductors can be represented by the following equation: ϵ = − L ΔI / Δt

1. Which of the following statements best explain the effects of the negative sign in front of the equation?

a. This equation is not accurate.

b. The negative sign produces an induced voltage that always opposes the change in the magnetic flux.

c. The negative sign has no effect. Only the absolute value of the value is considered.

d. The negative sign produces a constantly decreasing induced voltage.

2. If the current flowing in the coils is a sinusoidal signal I=I0sin(ωt)  which of the following statements best describes the amplitude of the generated voltage ϵ as the frequency ω increases? 

a. The amplitude of ϵ will not change as long as I0 is constant 

b. The amplitude of ϵ will increase because the same magnitude of current changes in shorter period of time     

c. The amplitude of ϵ will decrease because the same magnitude of current changes in longer period of time 

d. The amplitude of ϵ will decrease because the magnitude of the current will decrease

e. The amplitude of ϵ will increase because the magnitude of the current will increase

3. If the current flowing in the coils is a sinusoidal signal I=I0sin(ωt)  which of the following statements best describes the amplitude of the generated voltage ϵ as a function of time when ω and I0 are constant?  

a. The magnitude of ϵ is largest when the current is zero because this is where the largest change in ΔI occurs

b. The magnitude of ϵ is largest when the current is at minimum because of the minus sign relating ϵ and the change in current     

c. The magnitude of ϵ does not change with time when ω and I0 are constant

d. The magnitude of ϵ is largest when the current reaches maximum because this is where the largest change in ΔI occurs