Question

A tennis ball is dropped on to the floor from a height of 4m. it rebounds to a height of 3m. if the ball was in contact with the floor for 0.01s, what was it's average acceleration during contact ?

Answer 1

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A ball dropped on to floor from a height of...

A ball dropped on to floor from a height of 10m rebounds to a height of 2.5m. If the ball is in contact with the floor for 0.02s, its average acceleration during contact is?  

3 years ago

Answers : (2)

Divide it into two parts
First find the value of velocity when it will going to collide with the floor let say it is v1
secondly find out the velocity INITIAL ONE for the second part taking your displacement 2.5m let say it is v2
Now take t=0.02s take initial velocity to be equal to (-v1)
final velocity to be equal to v2 apply the first equation of motion and find the acceleration.

3 years ago

g=9.8m/s^2

u=0

v^2/19.6=10

v=14m/s

while bouncing back

0^2-u^2/-19.6=2.5

u^2=49

u=7m/s

time in contact=0.02s

therefore, (v-u)/t=14-7/0.02=350m/s^2

a=350m/s^2