@TuringTest

Ball A is dropped from the top of a building of height h at the same instant that ball B is thrown vertically upward from the ground. When the balls collide, they are moving in opposite directions, and the speed of A is 6 times that of B. At what height does the collision occur? (Use any variable or symbol stated above as necessary.)
I don't get it, two people tried it, we both got 4h/t. That's wrong.

Question

@TuringTest 

Ball A is dropped from the top of a building of height h at the same instant that ball B is thrown vertically upward from the ground. When the balls collide, they are moving in opposite directions, and the speed of A is 6 times that of B. At what height does the collision occur? (Use any variable or symbol stated above as necessary.)
I don't get it, two people tried it, we both got 4h/t. That's wrong.

amistre64 · Answer

what is the formula for collision in this case?

agent47 · Answer

this is what I did:
u - initial velocity, v - final velocity.
y - height from the bottom
u_a = 0
V_a = -6V_b
at collision, y_a=y_b

agent47 · Answer

and h - height of the building

amistre64 · Answer

are the speeds stated the value @ collision? or after collision?

agent47 · Answer

at collision, I'm assuming

amistre64 · Answer

then I think I got a visual of it

agent47 · Answer

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