What happens to an electric current produced from an electromagnet when the direction of the magnetic field changes?
a. the current stops.
b. the current increases.
c. the direction of the electric current changes.
d. the current decreases.
e.
the direction of the electric current stays the same.

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?

Ascientist wants to test ways to reduce pollution in lake . what is the bestway of doing this