How many miles an hour should a person perform when power walking

What are two different ways you could find the value of a? explain these methods.

Two point charges are on the y axis. a 3.90-µc charge is located at y = 1.25 cm, and a -2.4-µc charge is located at y = −1.80 cm. (a) find the total electric potential at the origin. v (b) find the total electric potential at the point whose coordinates are (1.50 cm, 0). v

Convection currents are caused by differences in what two things?