I do not know how to set up the problem to solve for height.

Physics
Tutor: None Selected Time limit: 1 Day

A ball is thrown up at initial speed of 25 m/s at the same time a ball is dropped from a building 14 m high. when will they both be the same height?

Jul 31st, 2014

One ball is thrown vertically at 25 m/s.

The other ball is let go at a height of 14 m, at a speed of 0 m/s.

We need to realize that gravity will increase the speed of the ball that is dropped and gravity will decrease the speed of the ball that goes up.

Imagine the balls meet at a height h.

Then the ball that is thrown up travels:

h=vot-1/2at^2

h=25t-1/2gt^2 EQN 1

During this same amount of time, t,

the ball falling will travel:

h-15=vot+1/2at^2

h-15=0+1/2(-g)^2

h=15-1/2gt^2 EQN 2

Substitute for h:

25t-1/2gt^2=15-1/2gt^2

25t=15

t=0.6 seconds 

This is the correct answer. I guarantee it.

I can solve many more problems like this. Let me know when you need help for these types of problems.


Jul 31st, 2014

Did you know? You can earn $20 for every friend you invite to Studypool!
Click here to
Refer a Friend
...
Jul 31st, 2014
...
Jul 31st, 2014
Dec 11th, 2016
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer