Max

Question 1

What does the Faraday law express, qualitatively speaking?

Answer 1

The Faraday law equates the change in potential V around a loop to the total flux through the surface bounded by that loop.
Is effectively implies that a changing magnetic field produces a current.

Question 2

What does the ampere law state, qualitatively?

Answer 2

The Ampere law in integral form essentially states that a moving charge (or collection of charges/current) produces a magnetic field circulating around it.

Question 3

What is the continuity equation for charge?

Answer 3

Div.J = -d[charge density wrt(r)]/dt

Where d is a partial differential, and J is current density. This essentially says that the divergence (change)of current density is equal and opposite to the change in charge density with respect to time.

Question 4

What does the Poynting vector dictate?

Answer 4

The Poynting vector dictates the direction of propagation of a wave.

Question 5

What is the Poynting vector?

Answer 5

N = EXH

Question 6

What is the time-averaged power per unit area in the wave (as found from the Poynting vector components)?

Answer 6

|N|_average = ExH*/2

Question 7

What is the relationship between E and H?

Answer 7

|E|/|H| = characteristic impedance ‘nu’