I drop a 60-g golf ball from 2.0 m high. It rebounds to 1.5 m. How much energy is lost()
A. 0.29 J
B. 0.50 J
C. 0.88 J
D. 1.0 J
E. 2.0 J
F. 1.5 J
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A 550 N physics student stands on a bathroom scale in an 850 kg (including the student) elevator that is supported by a cable. As the elevator statts moving, the scale reads 450 N. The acceleration of
A. 17.82m/s^2, upward
B. 17.82m/s^2, downward
C. 1.78m/s^2, upward
D. 1.78m/s^2, downward
A professional skier reaches a speed of 56 m/s on a 30° ski slope. Ignoring friction, what was the minimum distance along the slope the skier would have had to travel, starting from rest()
A. 110 m
B. 160 m
C. 320 m
D. 640 m
A girl and her bicycle have a total mass of 40.0 kg. At the top of the hill her speed is 5.0 m/s, and her speed doubles as she rides down the hill. The hill is 10.0 m high and 100 m long. How much kin
A. 2 420 J
B. 1 500 J
C. 2 000 J
D. 3 920 J
E. 4 920 J
F. 1 920 J
The quantity of work equal to one joule is also equivalent to which of the following()
A. watt
B. watt /s
C. watt∙s
D. watt /s^2