Dept. of Physics & Astronomy

Office: Watanabe Hall, Rm. 426, (808) 956-2922

E-mail: nassir @ hawaii.edu

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**Part A**

**1.** C

**2a.** B

**2b.** 6.00 x 10^-3 kg

**3.** E

**4.** D

**5.** B

**6.** D

**7a.** B

**7b.** A

**8a.** B

**8b.** B and D

**9a.** C

**9b.** E

**Part B**

**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).