"At a post office, a package of mass 1.3 kg is pushed down a slanted chute with an initial speed of 1.8 m/s. The upper end of the chute is 4 m above the floor. When it reaches the floor, the package has a speed of 0.9 m/s. Determine the energy lost through resistance and friction with the chut

(a) How high a hill can a car coast up (engine disengaged) if friction is negligible and its initial speed is 74.0 km/h? _______ m (b) If, in actuality, a 750 kg car with an initial speed of 74.0 km/h is observed to coast up a hill to a height 9.0 m above its starting point, how much thermal energy was generated by friction? ________ J  (c) What is the average force of friction if the hill has a slope 2.5° above the horizontal? ________ N (down the slope)

A box is given a push across a horizontal surface. The box has a mass m, the push gives it an initial speed of 2.40 m/s, and the coefficient of kinetic friction between the box and the surface is 0.140. (a) Use energy considerations to find the distance (in m) the box moves before it stops. m (b) What If? Determine the stopping distance (in m) for the box if its initial speed is doubled to 4.80 m/s. m

In the figure, a 3.97 g ice flake is released from the edge of a hemispherical bowl whose radius ris 13.7 cm. The flake-bowl contact is frictionless. (a) How much work is done on the flake by the gravitational force during the flake's descent to the bottom of the bowl? (b) What is the change in the potential energy of the flake-Earth system during that descent? (c) If that potential energy is taken to be zero at the bottom of the bowl, what is its value when the flake is released? (d) If, instead, the potential energy is taken to be zero at the release point, what is its value when the flake reaches the bottom of the bowl? (a) Number (b) Number -5.34e-3 (c) Number 5.34e-3 (d) Number 5.34e-3 Units Units Units Ice flake- Mik Units J