Hi, A time-varying (sinusoidal) voltage source is applied to a parallel plate capacitor of length d. Then the E field will vary according to E(t) = V(t)/d. However, this suggests that, for any given time, the E field is constant with respect to spatial coordinates. Therefore, the curl of E is zero. The time-varying E field will produce a time-varying B field according to Maxwell's equations. The derivative of B with respect to time will be non-zero. Therefore, the curl of E is non-zero. I know that the second statement is correct and the first is incorrect. Why is the first statement incorrect?