Why does a satellite in a circular orbit travel at a constant speed?

a)there is a force acting opposite to the direction of the motion of the satellite.
b)there is no component of force acting along the direction of motion of the satellite.
c)the gravitational force acting on the satellite is balanced by the centrifugal force acting on the satellite.
d)the net force acting on the satellite is zero.

Imagine an isolated positive point charge q (many times larger than the charge on a single proton). there is a charged particle a (whose charge is much smaller than charge q) at a distance from the point charge q. on which of the following quantities does the magnitude of the electric field created by charge q at particle a's position depend? check all that apply.the type of the charge on the charged particle athe relative orientation between q and a (while the distance between q and a is fixed)the specific location of the charged particle a (while the distance between q and a is fixed)the amount of the charge on the point charge qthe specific location of the point charge q (while the distance between q and a is fixed)the distance between the point charge q and the charged particle athe amount of the charge on the charged particle a