Why Is the Work Done by Weight Zero When Pushing a Box Horizontally?

  • Thread starter Thread starter 01010011
  • Start date Start date
  • Tags Tags
    Work Work done
Click For Summary
SUMMARY

The work done by the weight of a box when pushed horizontally is zero because the weight acts vertically downward, while the applied force and displacement are horizontal. In this scenario, a box weighing 100N is pushed with a force of 40N over a distance of 2m, resulting in 80N of work done by the applied force. The concept of work in physics is defined as the product of force and displacement in the direction of the force, which explains why the vertical weight does not contribute to work in this case.

PREREQUISITES
  • Understanding of vector quantities in physics
  • Knowledge of the work-energy principle
  • Familiarity with Newton's laws of motion
  • Basic grasp of force, displacement, and their relationship
NEXT STEPS
  • Study the work-energy theorem in classical mechanics
  • Learn about vector decomposition in physics
  • Explore scenarios involving inclined planes and their effects on work
  • Investigate the role of friction in work done on objects
USEFUL FOR

Students studying physics, educators teaching mechanics, and anyone interested in understanding the principles of work and energy in physical systems.

01010011
Messages
48
Reaction score
0

Homework Statement


A box of weight 100N is pushed a distance or displacement of 2m with a force of 40N. What is the work done on the box by i) the weight and ii) by the 40N force?

Homework Equations


Work = force * distance

The Attempt at a Solution


i) The work done on the box by weight = 0 (if this is correct, why?)

ii) The work done on the box by the 40N force
Work = force * distance
Work = 40 * 2
Work = 80N
 
Physics news on Phys.org
Work, force, and displacement are vectors. Can you figure out "why" from there?
 
I'll just say ths, work done by weight is 0 because that fat box did not helping you out AT ALL

Now, if it was on an incline sliding down as you pushed it..
 
Jack21222 said:
Work, force, and displacement are vectors. Can you figure out "why" from there?

Let me see... weight is acting vertically downwards, while force and displacement are acting horizontally. Therefore the weight had no influence on the force and displacement?

cronxeh said:
I'll just say ths, work done by weight is 0 because that fat box did not helping you out AT ALL

Now, if it was on an incline sliding down as you pushed it..

Thanks very much, you made it clearer
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
854
  • · Replies 4 ·
Replies
4
Views
2K
Replies
8
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
Replies
3
Views
2K
  • · Replies 7 ·
Replies
7
Views
10K
  • · Replies 3 ·
Replies
3
Views
938
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K