Which of these events is an example of the doppler shift?
the amplitude of a wave on a string increases as the frequency decreases.
the amplitude of sound from a tuning fork decreases due to damping.
the frequency of light from a star increases as it moves toward us.
the intensity of an electromagnetic wave increases with the field strength.
the velocity of an electromagnetic wave changes as its medium changes.

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

The magnitude of the magnetic field at a certain distance from a long, straight conductor is represented by b. what is the magnitude of the magnetic field at twice the distance from the conductor? a. at twice the distance, the magnitude of the field is 4b.b. at twice the distance, the magnitude of the field is 2b.c. at twice the distance, the magnitude of the field is b/2.d. at twice the distance, the magnitude of the field is b/4.e. at twice the distance, the magnitude of the field remains equal to b.

State the below theories and give the name of the writer of the theory 1. wave theory 2. quantum theory 3. corpuscular theory 4. electromagnetic theory