Two charged pith balls are suspended on very light 120 cm strings. Each has a mass of 10.0 g. Assume the angle the threads make from the vertical is θ = 15o and that the balls are in equilibrium. Draw a free-body diagram for one of the pith balls and clearly label all forces with magnitude and direction. Assuming the pith balls are equally charged, what is the charge on each ball?

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.