Aballoon rubbed against denim gains a charge of −7.0 µc. what is the electric force between the balloon and the denim when the two are separated by a distance of 3.0 cm? (assume that the charges are located at a point.) the value of the coulomb constant is 8.98755 × 109 n · m 2 /c 2 . include direction of the force. answer in units of n.

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods