1. A powerful motorcycle can accelerate from rest to26.8m/s (60mi/h) in only1.90s. (For each answer, enter a number.)

(a)What is its average acceleration in m/s²? __14.11__m/s²

(b)How far (in m) does it travel in that time? __?__m

2. Calculate the height (in m) of a cliff if it takes 2.41 s for a rock to hit the ground when it is thrown straight up from the cliff with an initial velocity of 8.05 m/s. (Enter a number.) ____ m

(b)How long (in s) would it take to reach the ground if it is thrown straight down with the same speed? (Enter a number.) ____ s

3. A ball is kicked with an initial velocity of 15 m/s in the horizontal direction and 13 m/s in the vertical direction. (Assume the ball is kicked from the ground. For each answer, enter a number.)

(a)At what speed (in m/s) does the ball hit the ground? ____ m/s

(b)For how long (in s) does the ball remain in the air? ____ s

(c)What maximum height (in m) is attained by the ball? ____ m

4. Near the end of a marathon race, the first two runners are separated by a distance of 45.0 m. The front runner has a velocity of 3.45 m/s, and the second a velocity of 4.25 m/s.

(a)What is the velocity of the second runner relative to the first? (Enter a number. Enter your answer in m/s faster than the front runner.) ____ m/s faster than the front runner

(b)If the front runner is 250 m from the finish line, who will win the race, assuming they run at constant velocity?

The second runner will win.

The first runner will win.

(c)What distance (in m) ahead will the winner be when she crosses the finish line? (Enter a number.) ____m