Question

If a ball is thrown directly upwards with twice the initial speed of another, how much
higher will it be at its apex?
A) 8 times D) 2 times
B) 4 times E) 2 times
C) 2 2 times

Please show any equations that are used :)

Answer 1

You don't need an equation to answer this. The ball thrown at twice the velocity has four times the kinetic energy of the slower ball (assumiung that they have the same mass). The distance that the ball rises is proportional to the initial kinetic energy. So it rises four times as high.

The same answer applies even if the masses are different. That is because

H(max) = Vo^2/(2*g)

Vo is the initial velocity