Answer Happy

6. A ball has a mass of 0.40 kg. Initially it is moving horizontally to the left at 10.0 m/s, but then it is hit. After the hit it is moving at 45° upward and to the right with a speed of 60.0 m/s. The direction of the acceleration is (measured from the horizontal)
7. A ball is attached to a string and twirled around in the horizontal plane in uniform circular motion as shown
in the figure below. Which of the free-body-diagrams may be correct for this ball?
6. A ball has a mass of 0.40 kg. Initially it is moving horizontally to the left at 10.0 m/s, but then it is hit. After the hit it is moving at 45° upward and to the right with a speed of 60.0 m/s. The direction of the acceleration is (measured from the horizontal) (a) 0 <ĐS10 (b) 10° <0 ≤25° (c) 25° <0<45° (d) 45° (e) None of the above 7. A ball is attached to a string and twirled around in the horizontal plane in uniform circular motion as shown in the figure below. Which of the free-body-diagrams may be correct for this ball? (a) (c) (d) LFF (c) (d) 8. A traveler on the Hayabusa shinkansen on route to Sendai is flipping a coin straight up. The train is traveling at 100.0 m/s and the traveler catches the coin again after the train traveled a distance of 200.0 m. The initial speed of the coin as seen by the traveler is (a) 2.50 m/s (b) 5.00 m/s (c) 10.0 m/s (d) 100 m/s 9. In a physics demonstration, an instructor "races" various bodies (all have the same mass and outer radius) that roll without slipping from rest down an inclined plane. The objects are: a solid ball, a solid cylinder, a thin-walled hollow ball, and a thin-walled hollow cylinder. Which object will reach the bottom first? (a) the solid ball (b) the solid cylinder (e) the thin walled hollow ball (d) the thin-walled hollow cylinder (e) can't tell from the information given