Steve is whirling a rubber cork, tied with a string to his finger, over his head as shown in the figure. the motion of the cork is similar to the motion of a planet in the solar system around the sun. which force in the solar system is similar to the tension in the string?
a) nuclear force
b) magnetic force
c) gravitational force
d) electrostatic force

Anybody wanna ? (picture included? )

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e

What causes the development of most clouds and precipitation in the atmosphere?