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A rubber ball is shot straight up from the ground with speed v0. Simultaneously, a second rubber ball at height h directly above the first ball is dropped from rest.

a. At what height above the ground do the balls collide? Your answer will be a symbolic expression in terms of v0, h, and g .
b.What is the maximum value of h for which a collision occurs before the first ball falls back to the ground?
c.For what value of h does the collision occur at the instant when the first ball is at its highest point?
Express your answer in terms of the variable v0

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Final answer:

The height at which the two rubber balls collide can be determined using equations of motion, with the maximum value of h found by considering the time it takes for the first ball to reach maximum height. For the collision to occur at the first ball's highest point, we use the time to reach maximum height to calculate h.

Step-by-step explanation:

To solve problems involving projectile motion and the collision of objects in vertical motion, we use equations of kinematics under the influence of gravity. Let's focus on the question at hand, involving two rubber balls - one being shot up and the other being dropped.

Height of Collision:

Let's denote the time of collision as t. For the first ball being shot up, the equation of motion is s = v0 * t - (1/2) * g * t^2. For the second ball, dropped from height h, the equation is s = h - (1/2) * g * t^2. Setting these equal to each other because they collide at height s and solving for t, we can then plug the time into one of the equations to find the height of collision.

Maximum Value of h:

The maximum value of h for which a collision occurs before the first ball falls back to the ground is when the first ball reaches its maximum height and starts to fall. This happens at t = v0 / g. We plug this time into the second ball's equation of motion to solve for h.

Value of h for Collision at Max Height:

For the collision to occur when the first ball is at its highest point, we use the time it takes the first ball to reach maximum height. As mentioned, this time is t = v0 / g, and since the ball is at maximum height, h equals the distance the first ball traveled which is (v0)^2 / (2g).

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