The Open Door Web Site
HOME PAGE BIOLOGY CHEMISTRY PHYSICS ELECTRONICS HISTORY HISTORY of SCI & TECH MATH STUDIES LEARN FRENCH STUDY GUIDE PHOTO GALLERY
ATOMIC and NUCLEAR ELECTRICITY and MAGNETISM MEASUREMENTS MECHANICS OPTICS PRACTICAL WORK QUESTIONS RELATIVITY THERMAL PHYSICS WAVES
PRACTICAL WORK
Google
Custom Search
Mechanics
 
Aim: to estimate the Coefficient of Restitution for a ball bouncing on the laboratory bench
When two objects collide, their coefficient of restitution gives a measure of the elasticity of the collision.
An totally elastic collision is one in which kinetic energy is conserved. 
In practice some k.e. is always converted into other forms.
Which other forms?
If we compare the relative velocity of the two objects just before the collision (velocity of approach, va) with their relative velocity just after the collision (velocity of separation, vs) we can see "how elastic" the collision was.
We therefore define the quantity the coefficient of restitution, e as follows
To use a sophisticated technical term, we are going to find out how bouncy the ball is!
Notice that e = 1 corresponds to a perfectly elastic and e = 0 a totally inelastic collision (the objects stick together).
 
Method
In order to estimate the height h2 to which the ball bounces, it is helpful to have two horizontal bars of adjustable positions, as shown below.
 
An alternative method might be to video the ball in front of a background with some kind of grid marked on it...
 
 By considering energy changes during the fall of the ball (gravitational potential energy to kinetic energy) and during the rebound of the ball (k.e. to g.p.e.), you will see how a value for e can be taken from a graph of h2 against h1.
 
SITE MAP
WHAT'S NEW
ABOUT
PRIVACY
COPYRIGHT
SPONSORSHIP
DONATIONS
ADVERTISING
 

© The Open Door Team
2016
Any questions or
problems regarding
this site should be
addressed to
the webmaster

David Hoult 2017

Hosted By
Web Hosting by HostCentric

 
SiteLock
 
 
Practicals Index Page