Three 3.0g {\rm g} balls are tied to 80-cm {\rm cm}-long threads and hung from a single fixed point. Each of the balls is given the same charge q q. At equilibrium, the three balls form an equilateral triangle in a horizontal plane with 20 cm {\rm cm} sides. What is q?

Heena wants to measure the volume of a ball that is 24 cm across. how should she set up her equation?

Arocket starts from rest and moves upward from the surface of the earth. for the first 10.0 s of its motion, the vertical acceleration of the rocket is given by ay = 12.80 m/s32t, where the +y-direction is upward. (a) what is the height of the rocket above the surface of the earth at t = 10.0 s? b) what is the speed of the rocket when it is 325 m above the surface of the earth?

Two balls, each with a mass of 0.5 kg, collide on a pool table. is the law of conservation of momentum satisfied in the collision? explain why or why not