An object A is thrown up with a velocity of 12m/s at the same time an object B of equal mass is thrown down with a velocity of 12m/s.
a. Which object will hit the ground first?
b. How will the final velocities of object A and B compare?
c. Which object will have a greater acceleration?

Explanation:

A)

Multiply the time by the acceleration due to gravity to find the velocity when the object hits the ground. If it takes 9.9 seconds for the object to hit the ground, its velocity is (1.01 s)*(9.8 m/s^2), or 9.9 m/s.

B)

If two particles are involved in an elastic collision, the velocity of the second particle after collision can be expressed as: v2f=2⋅m1(m2+m1)v1i+(m2−m1)(m2+m1)v2i v 2 f = 2 ⋅ m 1 ( m 2 + m 1 ) v 1 i + ( m 2 − m 1 ) ( m 2 + m 1 ) v 2 i .

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