A 140 kg hoop rolls along a horizontal floor so that the hoop's center of mass has a speed of 0.15 m/s. How much work must be done on the hoop to stop it? -5.15 J -1.15 J -4.15 J -2.15 J -3.15 J

A 0.25 kg ball rolls without slipping at a speed of 6.0 m/s. What is the total kinetic energy of the ball?

The ball launcher A large ball with mass mA =5kg falls from a height ℎ=2m into the scoop of a straight balance beam with a length of L=4.5m and mass mB​=10kg (see diagram). A small ball with mass mC​=1.4kg is located in a second scoop at the other end of the balance beam. The balance beam, at rest, makes an angle α=45∘ relative to the horizontal. After the impact of the large ball on the scoop, it remains there, and the balance beam starts to rotate. When the balance beam is horizontally aligned, a rod momentarily blocks the balance beam, and the small ball is expelled from its scoop. What will be the maximum height reached by the small ball after being expelled from its scoop relative to the horizontal position of the balance beam? (Consider the balls as point masses.)

A 140 kg hoop rolls along a horizontal floor so that the hoop’s center of mass has a speed of 0.150 m/s. How much work must be done on the hoop to stop it?