A 30-N stone is dropped from a height of 10 m and strikes the ground with a speed of 13 m/s. What average force of air friction acted on the stone as it fell?
A) 4.1 N
B) 2.9 N
C) 0.13 kN
D) 7.2 N
E) 1.2 N
A
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Light travels ________ in water than in air.
A. faster B. slower C. perpendicular to D. at the same speed
When you throw a ball, the work you do to accelerate it equals the kinetic energy the ball gains. If you do twice as much work when throwing the ball, does it go twice as fast?
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Because of time dilation, if a twin goes on a trip in a high speed rocket ship, when she returns home she will be younger than her twin sister who did not go on the trip
Indicate whether the statement is true or false
Explain interferometry and provide an example of an observatory that uses this technique
What will be an ideal response?