# Homework Help: Linear kinematics problem with limited variables.

1. Oct 14, 2015

### Btipold

A rock is dropped from a cliff of height h. At the same time a rock is thrown straight up from the bottom with an initial velocity. Assuming they meet, at what time will they meet.

V1 = 0
A = -9.82

Thats all you have across both rocks... is this even possible. You probably have to do some substitution equation and make ts equal each other. Idk.

2. Oct 14, 2015

### SteamKing

Staff Emeritus
Well, if you don't write down any equations which describe the motion of each rock, the solution to this problem will remain an eternal mystery.

3. Oct 15, 2015

### haruspex

Clearly the answer will depend on the velocity with which the lower rock is thrown. The question statement reads as though you were about to be given that velocity, but it's missing. Have you left something out?

4. Oct 15, 2015

### Noctisdark

They will meat if $x_1 = x_2$ where $x_1, x_2$ are the equation of motion of rock 1 and rock 2, can you figure out what these equation are ?