Answer to Question #283499 in Physics for Ella

Question

1. Two light sources are said to be coherent if they ___________

A. are of the same frequency.

B. are of the same frequency, and maintain a constant phase difference.

C. are of the same amplitude, and maintain a constant phase difference.

D. are of the same frequency and amplitude.

2. Coherent electromagnetic waves are not emitted by

A. two antennas connected to the same radio transmitter

B. two pinholes in an opaque shield over a sodium-vapor lamp

C. a pinhole in an opaque shield over a sodium-vapor lamp and its reflection in a mirror

D. two lasers

Answer 1

1. Two light sources are said to be coherent if they are of the same frequency, and maintain a constant phase difference.

2. Coherent electromagnetic waves are not emitted by two lasers.