A 30 kg box is placed on a skateboard and pushed across the room with a velocity of 4 m/s. The pusher applies more force, increasing the velocity to 10 m/s. How much work was done to move the box?

Asmall blob of putty of mass m falls from the ceiling and lands on the outer rim of a turntable of radius r and moment of inertia i0 that is rotating freely with angular speed ω0 about its vertical fixed-symmetry axis. (use any variable or symbol stated above as necessary.)

When an object is heated it contracts. a. true b. false

A0.580-kg rock is tied to the end of a string and is swung in a circle with a radius of 0.500 meters. the velocity of the rock is 4.50 m/s. what is the centripetal force acting on the rock? 15.5 n 5.22 n 69.8 n 23.5 n