Answer:
0·233 J
Explanation:
Given
Mass of the ball = 0·012 kg
Initially the ball is at a height of 2·5 m
As initially the ball is dropped, it's initial velocity will be equal to 0
Therefore initially it has zero kinetic energy and has only potential energy
∴ Initially total mechanical energy of the ball = potential energy of the ball
Initial potential energy of the ball = m × g × h
where
m is the mass of the ball
g is the acceleration due to gravity
h is the height of the ball
∴ Potential energy = 0·012 × 9·8 × 2·5 = 0·294 J
Velocity of the ball after striking the floor = 3·2 m/s
After striking the floor, the total mechanical energy = kinetic energy just after striking the floor
Kinetic energy = 0·5 × m × v²
where m is the mass of the ball
v is the velocity of the ball
∴ Kinetic energy of the ball = 0·5 × 0·012 × 3·2² = 0·061 J
Mechanical energy that is lost = 0·294 - 0·061 = 0·233 J
∴ Mechanical energy that the ball lost during its fall = 0·233 J
