Question

A ball is gently dropped from a height of 20 m onto a hard surface where it make an elas 1) Show that the speed of the ball just before hits the ground is 20m/s (g=10m/s2)

2) Why isn’t the accelera 3) Use axes below to sketch a graph of how the velocity of the ball varies with several bounces

Answer 1

20 m/s

Step-by-step explanation:

Use the position/displacement formula to find out how long the ball is in the air:

(distance) = (initial velocity)*(time) + (1/2)*(acceleration)*(time)^2

20 = 0*t + 1/2*10*t^2

t^2 = 4

t = 2 seconds

Use the velocity formula:

(final velocity) = (initial velocity) + (acceleration)*(time)

Vf = 0 + 10*2

Vf = 20 m/s