A tennis ball is dropped from 1.71 m above the ground. It rebounds to a height of 0.828m. With what velocity does it hit the ground? The acceleration of gravity is 9.8 m/s2. (Let down be negative.) Answer in units of m/s.

Asmall metal bar, whose initial temperature was 10° c, is dropped into a large container of boiling water. how long will it take the bar to reach 70° c if it is known that its temperature increases 2° during the first second? (the boiling temperature for water is 100° c. round your answer to one decimal place.) sec how long will it take the bar to reach 98° c? (round your answer to one decimal place.)

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.

Which one of the following represents the reduced forms of the two major electron carriers? nadh and fadh2 nad+ and fadh2 nad+ and fad nadh and fad