If a ball rolls off a cliff that is 40.0 meters tall and lands 10.0 meters from the base of the cliff, with what initial horizon

Question

3 years ago

13

tal velocity did the ball roll off the cliff? Neglect air resistance.
A.2.80 m/s
B.3.00 m/s
C.3.50 m/s
D.4.20 m/s

1 answer:

IrinaVladis [17] · Answer 1 · 2022-08-08T09:57:22+03:00

Option (c) is correct.

Explanation:

initial velocity along vertical=0

velocity along horizontal Vx

acceleration along the vertical=9.8 m/s²

displacement along vertical,h=40 m

distance along horizontal= 10 m

using the kinematic equation

h= vi*t + 1/2 g t²

40=0(t) + 1/2 (9.8)t²

t²=8.163

t=2.857 s

now the displacement along vertical= x= Vx* t

10=Vx (2.857)

Vx=3.5 m/s