If we rub a rubber rod against a piece of fur the rod gains a negative change. Why does the rod have a negative charge?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

If forces acting on an object are unbalanced. true or false

Steelhead trout migrate up stream to spawn.occasionally they need to leap up small waterfalls to continue their journey. fortunately, steelhead are remarkable jumpers, capable of leaving the water at a speed of 8.0 m/s. a. what is the maximum height a steelhead trout can jump? b.leaving the water at 8.0 m/s, the trout lands on top of the water fall 1.8 m high. how long was it in the air?