Answer:
n = 5 approx
Explanation:
If v be the velocity before the contact with the ground and v₁ be the velocity of bouncing back
= e ( coefficient of restitution ) = 
and

h₁ is height up-to which the ball bounces back after first bounce.
From the two equations we can write that


So on

= .00396
Taking log on both sides
- n / 2 = log .00396
n / 2 = 2.4
n = 5 approx
Answer:
+9.8m/s^2
Explanation:
The rate of gravity of the object is constant thriughout the surface of the earth.
For falling object, the rate of gravity is positive since the body is coming down (falling)
The rate of gravity is negative if the body is going up
The constant value for acceleration due to gravity is 9.8m.s^2
Since the object is falling, hence the acceleration due to gravity is positive.
Rate of gravity working on the object will be +9.8m/s^2