posted by suraj suwal .
An object is thrown downward with an initial
speed of 10 m/s from a height of 49 m above
the ground. At the same instant, a second
object is propelled vertically up from ground
level with a speed of 29 m/s .
At what height above the ground will the
two objects pass each other? The acceleration
of gravity is 9.8 m/s
Answer in units of m
First solve for the time when they are at the same height.
49 - 10 t - 4.9 t^2 = 29 t - 4.9 t^2
The t^2 terms cancel.
39t = 49
t = 1.2564 seconds
Then, use the height vs. time equation for either object for the vertical height at that time.
Y = 29t - 4.9 t^2 = 28.7 meters