Impact energy

  • Thread starter kepler
  • Start date
  • #1
29
0
Hi,

Supose I drop a body of 7 Kg from a height of 2 meters. Is the impact energy equal to:

E = m * g * h = 7 * 9.81 * 2 = 137,34 Joules ?

And if it is, is the kinetic energy equal to this ammount?

Kind regards,

Kepler
 

Answers and Replies

  • #2
Doc Al
Mentor
45,017
1,291
I'm not familiar with the the term "impact energy" in this context, but the energy that you calculated is the kinetic energy of the object after falling 2 meters.
 
  • #3
Gokul43201
Staff Emeritus
Science Advisor
Gold Member
7,051
18
The impact energy is the total (elastic +plastic) strain energy absorbed by the deforming body. It is usually a large part of KE the body had before impact. Parts of the KE also go into heat and sound, but these fractions are usually small and are typically neglected.

So, the answer to the first question is: Yes, that's pretty close to the impact energy.

Note : The above is the definition of impact energy for an event. The standard definition of impact energy, however, is for a material. In that context, the impact energy is defined as the total strain energy absorbed until fracture (but that's not relevant to this specific problem).
 

Related Threads on Impact energy

  • Last Post
Replies
1
Views
2K
Replies
3
Views
878
  • Last Post
Replies
5
Views
1K
Replies
16
Views
992
Replies
7
Views
545
Replies
2
Views
600
Replies
5
Views
5K
Replies
14
Views
586
Replies
4
Views
695
Top