You have been asked to demonstrate the power of electric forces to a class of fifth
graders. For the demonstration, you charge a
balloon by rubbing it with animal fur. Then
you hold the balloon a few centimeters above
the head of a student with long hair.
1. Describe what will happen to the student's
hair as you bring the balloon closer and closer
to it.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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show the wavelengths of a wave. show the crests of a wave.

it has to be b, about 97 percent.

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