A ball of mass 0.75kg moving horizontally at 5m/s strikes a vertical wall and rebounds with a speed of 2m/s.find (a)what is the impulse received by the ball?(b)calculate the coefficient of restitution(c)calculate the kinetic energy of the ball before and after collision.
impulse is change of momentum
.75 * 7 kg m/s or Newton seconds
final speed/initial speed = 2/5
(1/2) .75 (25)
(1/2) .75 (4)
I don't understand
To answer these questions, we need to understand the concepts of impulse, coefficient of restitution, and kinetic energy.
(a) To find the impulse received by the ball, we can use the formula:
Impulse = Change in momentum
The momentum of an object is defined as the product of its mass and velocity. In this case, the ball has a mass of 0.75 kg and is initially moving horizontally at 5 m/s. After colliding with the wall, it rebounds with a speed of 2 m/s.
The initial momentum of the ball can be calculated as:
Initial momentum = mass × initial velocity
= 0.75 kg × 5 m/s
The final momentum of the ball can be calculated as:
Final momentum = mass × final velocity
= 0.75 kg × (-2 m/s) # Note that the velocity is negative because the ball is rebounding in the opposite direction.
Now, we can find the change in momentum:
Change in momentum = Final momentum - Initial momentum
(b) The coefficient of restitution is a measure of the elasticity of a collision. It is defined as the ratio of the relative velocity of separation to the relative velocity of approach.
Coefficient of restitution = (Final velocity - Initial velocity) / (Initial velocity - Initial velocity)
In this case, the relative velocity of separation is the final velocity of the ball after the collision (2 m/s) minus the initial velocity of the ball before the collision (5 m/s). The relative velocity of approach is the initial velocity of the ball before the collision (5 m/s) minus the initial velocity of the ball after the collision (-2 m/s).
(c) The kinetic energy of an object is defined as one-half the product of its mass and the square of its velocity.
The initial kinetic energy of the ball can be calculated as:
Initial kinetic energy = 0.5 × mass × (initial velocity)^2
The final kinetic energy of the ball can be calculated as:
Final kinetic energy = 0.5 × mass × (final velocity)^2
I hope this clarifies how to approach the problem! If you need further assistance with the calculations, please let me know.