Derive the relationship between, MA, VR and Efficiency.

When you turn on a battery-operated device, an electrical circuit is

Abatter hits a 0.140-kg baseball that was approaching him at 30 m/s and, as a result, the ball leaves the bat at 40 m/s in the reverse of its original direction. the ball remains in contact with the bat for 2.0 ms. what is the magnitude of the average force exerted by the bat on the ball?

Which system of units is used by only a small number of countries in the world, including the u. s.