A long, straight wire carries a 13.0-A current. An electron is fired parallel to this wire with a velocity of 250 km/s in the same direction as the current, 2.00 cm from the wire. (a) Find the magnitude and direction of the electron’s initial acceleration.
(b) What should be the magnitude and direction of a uniform electric field that will allow the electron to continue to travel parallel to the wire?
(c) Is it necessary to include the effects of gravity? Justify your answer.

Aplane travels 1000 miles in 5 hours .what is the planes average speed?

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.

Awave with a frequency of 500 hz is traveling at a speed of 100 m/s.what is the wavelength?