Return to PHYS 151 Exam & Answers page
2b. 6.00 x 10^-3 kg
8b. B and D
1a. v_0x = 24.7 m/s, v_0y = 24.7 m/s
(24.75 m/s can be used in subsequent parts, to prevent roundoff error)
1b. 31.2 m
1c. When x = 100 m, t = 4.04 s. At that time, y = 19.9 m. The fence is only 10.0 m tall, so the ball DOES clear the fence.
OR: When y = 10.0 m, t = 0.443 s (on ascent) and t = 4.60 s (on descent). At t = 4.60 s, the ball has reached x = 114 m. Since the fence is only 100 m away, the ball DOES clear the fence.
2a. +22.5 m/s
2b. Straight downward-sloping line from (0 s, +22.5 m/s) to (15 s, -15 m/s);
straight horizontal line from there to (25 s, -15 m/s);
upward-sloping line from there to (35 s, 0 m/s);
straight horizontal line from there to (40 s, 0 m/s).