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Why is work not said to be done by a boy who is pushing a wall?
Wiki User
∙ 14y ago
Because in the case of an applied force, work = force x distance, and in this case the distance is zero - the force is not applied over a longer distance.
Any energy spent by the boy for applying the force is wasted - converted into heat.
For extra credit:
Unless the wall is perfectly inelastic (not much is perfect) it will move a little (a very little) so some work is done. Just so little it is hard to notice. Like when someone types their homework question into one of these question/answer sites and doesn't think about what they have been told during lesson time or what they have been asked to read. Lazy minds are just lumps of fat.
Wiki User
∙ 14y ago
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Is pushing up against a wall doing work?
No,beacuse the wall is oushing against you. For work to be done, it has to be done in the same direction.
Is it tiring to push hard against a solid wall even if no work is done?
Not sure if this is a real physics question... but yes, pushing against a wall is tiring even though no "work" is being done. Its isometric conditioning. Think of this: Put your hands in front of you and press them together as hard as you can for as long as you can. This will tire you out pretty quick.
A student pushes against a wall with 20 N of force and the wall does not move In this situation?
Obviously 20 N of force, right? Since neither object goes anywhere.
What occur in order for work to be done?
In order for work to be done there must be a Force F pushing over a distance D. Work=Force x Distance Work only is done in the direction of the Force.
How much work is done by a force of 500N on a stationary brick wall?
none. work is only done when energy is exchanged
Is pushing up against a wall doing work?
No,beacuse the wall is oushing against you. For work to be done, it has to be done in the same direction.
What is he definition of work?
Work is the product of a force and the distance through which it acts in the direction of the force. In order for work to be done, the object must move in the direction of the force. If you push on a brick wall until you exhaust yourself and the wall doesn't move, you have not done any work. If you push on a box and it moves in the direction that you are pushing it, you have done work.
Is it tiring to push hard against a solid wall even if no work is done?
Not sure if this is a real physics question... but yes, pushing against a wall is tiring even though no "work" is being done. Its isometric conditioning. Think of this: Put your hands in front of you and press them together as hard as you can for as long as you can. This will tire you out pretty quick.
A student pushes against a wall with 20 N of force and the wall does not move In this situation?
Obviously 20 N of force, right? Since neither object goes anywhere.
Is pushing up on box as you carry it down the hall considered work done?
No, it is not.
What occur in order for work to be done?
In order for work to be done there must be a Force F pushing over a distance D. Work=Force x Distance Work only is done in the direction of the Force.
Is work done if you push a car that has run out of gas?
Yes. The work is being done by whoever is pushing rather then the engine, but work is being done. Any time a force is applied through a distance, work is being done.
How much work is done by the surface molecules pushing upward on the object when it moved horizontally?
If there is no vertical motion, then no work is done by any vertical forces.
How much work is done by a force of 500N on a stationary brick wall?
none. work is only done when energy is exchanged
When is a thermodynamic work said to be positive?
In thermodynamics, work done by a system on its surroundings or another system is said to be positive.
Is it possible for force to act on a object with out work being done?
No. The centripetal force will change the velocity of the object, but it won't make it go any faster - so it won't transfer energy to the object. Another way to look at this is that the centripetal force is at right angles to the movement. Since the cosine of the angle is zero, the vector dot product (force x distance x (cosine of angle between the two)) is also zero.
What are examples of work done?
Work is said to be done where certain displacement is involved. Ex. Of work not done is Coolie carrying Load on his head..
