• Support PF! Buy your school textbooks, materials and every day products Here!

Finding PE given mass, distance, and energy lost.

  • #1

Homework Statement


I'm supposed to find the potential energy at the start of a system for a vehicle given that the mass is 4000kg, the total distance traveled is 800m, and 3/4 of the total energy is lost to heat and friction by the end of the distance traveled (it's assumed that the vehicle starts from rest). Now, I know I can easily solve for a variable, but given this information I'm under the impression that I need to get a numerical answer. It's frustrating because I feel like I am not taking something into account.

Homework Equations


PE = mgh

The Attempt at a Solution


I've come up with really just substitution for the variables, so:
PE = 4500kg*9.8m/s^2*h.
 

Answers and Replies

  • #2
jbriggs444
Science Advisor
Homework Helper
2019 Award
8,343
3,180
Is that all of the information that you have been given? It's not enough.
 
  • #3
Is that all of the information that you have been given? It's not enough.
Unfortunately, yes. I have scoured over my worksheet - nothing. I've since emailed my professor, but any further input you guys have would be appreciated.
 
  • #4
jbriggs444
Science Advisor
Homework Helper
2019 Award
8,343
3,180
You could try finding a formula for potential energy in terms of some other variable. For instance, as a function of speed at the end of the run.
 

Related Threads on Finding PE given mass, distance, and energy lost.

Replies
1
Views
9K
  • Last Post
Replies
2
Views
5K
Replies
2
Views
2K
  • Last Post
Replies
2
Views
27K
Replies
3
Views
1K
Replies
1
Views
1K
Replies
4
Views
554
  • Last Post
Replies
3
Views
3K
Top