Aball rolls off a tall shelf with a horizontal speed of 2 m/s. the shelf is 1.29 m high. how long will it take for the ball to strike the ground?

consider the motion of the ball in vertical direction after it rolls off the shelf

v₀ = initial velocity in vertical direction just after it leaves shelf = 0 m/s

Y = vertical displacement = height of the shelf = 1.29 m

a = acceleration of ball = acceleration due to gravity = 9.8 m/s²

t = time to strike the ground

Using the kinematics equation

Y = v₀ t + (0.5) a t²

1.29 = (0) t + (0.5) (9.8) t²

1.29 = 4.9  t²

t² = 1.29/4.9

t² = 0.2633

t = √ 0.2633

t = 0.51 sec

hence the ball strike the ground after 0.51 sec

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

hope this ! : )

answer: a. same unit

explanation: