Will give brainliest, 25 points: A cannonball is launched straight up from the ground at 13.5 m/s. How much time is the cannonball in the air (hangtime)?

Time in air t = 1.38 second (Approx)

Explanation:

Given:

Initial speed u = 0 m/s

Final speed v = 13.5 m/s

Find:

Time in air t

Computation:

v = u + gt

g = 9.8 m/s²

13.5 = 0 + (9.8)(t)

13.5 = 9.8 t

t = 13.5 / 9.8

t = 1.3777 second

Time in air t = 1.38 second (Approx)

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.