Back Unit A Test Question 1 Not yet answered Marked out of 1.00 A ball of mass 2.0 kg falls vertically and hits the ground with speed 7.0 m/s as shown below: Flag question 7.0 ms (In the above diagram, ms means m/s.) 3.0 ms Time left 2:59:20 The ball leaves the ground with a vertical speed of 3.0 m/s. The magnitude of the change in momentum of the ball, correct to two significant figures, is Ns. Next page Back Physics 30/Unit A Test Unit A Test Time left 2:58:55 Question 2 Not yet answered An empty freight car of mass m coasts along a track at 2.00 m/s until it couples to a stationary freight car of mass 2m. The final speed of the two freight cars immediately after the collision is Marked out of 1.00 A. 1.50 m/s B. 1.33 m/s Flag question C. 1.15 m/s Previous page D. 0.667 m/s Next page Question 3 Not yet answered Marked out of 1.00 Flag question Previous page Time left 2:58:47 The graph below approximates the net force exerted westward on a 9.71 g bullet in the barrel of a hunting rifle after it is fired. Note that the time axis begins at 0.5 x 104 s. Force in ktl 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 1 Force and Time for a Rifle Bullet 2 13 14 15 16 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (x 10s) Using the data from the graph, the impulse imparted to the bullet from the time 1 x 104 s to 13 x 10-4 s is A. 7.2 NS [W] B. 3.6 N s [W] C. 10.8 N s [W] D. 14.4 NS [W] Next page