All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Science
Rise of an object-Physics (Posted on 2003-04-01) Difficulty: 3 of 5
If a 7kg object is thrown straight upwards at a speed of 10m/s(meters per second)

To what height will it rise? note: gravitational constant = -9.8m/s

See The Solution Submitted by Lucifer    
Rating: 3.2308 (13 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution Puzzle Solution : Method II Comment 16 of 16 |
(In reply to Puzzle Solution by K Sengupta)

Let us denote the kinetic energy of the ball in its course of the motion before coming to rest as K(E). We will represent the potential energy of the ball after completing its upward journey as P(E).

Then, K(E) =  (1/2)*m*v^2, and: P(E) = m*g*h, where:
g = absolute magnitude of the gravitational constant = 9.8 m/s
v = initial velocity of the ball
h = the height to which the ball will rise.

In terms of the laws of conservation of energy, we must have:

K(E) = P(E)
-> (1/2)*m*v^2 = m*g*h
-> h = (v^2)/(2*g) = 100/(2*9.8) ~ 5.1

Consequently, the ball will rise to a height of approximately 5.1 meters .


  Posted by K Sengupta on 2008-12-04 06:17:37
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (2)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information