The strength of a magnetic field created by current in a wire can be increased by: A. Decreasing the current in the wire.
B. Using longer wire.
C. Using shorter wire.
D. Wrapping the wire into a coil.

Awoman stands a distance d from a loud motor that emits sound uniformly in all directions. the sound intensity at her position is an uncomfortable 2.0×10-3 w/m2. at a distance 2.6 times as far from the motor, what are (a) the sound intensity and (b) the sound intensity level relative to the threshold of hearing?

Lightning is an example of what phenomenon? a release of a large amount of energy an absorption of a large amount of energy a natural electric circuit a natural electric current

What is the increase in density of a medium due to wave travel?