1. When you throw a pebble straight up with initial speedV, it reaches a maximum height H with no airresistance. At what speed should you throw it up vertically so itwill go twice as high?
a. Insufficient information
b. 18 V
c. V sqrt(2)
d. 4 V
e. 8 V
2. A 60.0-kg man stands at one end of a 20.0-kg uniform 10.0-mlong board. How far from the man is the center of mass (or centerof gravity) of the man-board system?
a. 1.25m
b. 5m
c. 9m
d. 2.5m
