For work to be done, the force must be applied in the same direction that the object moves. If a force is applied in a different direction than the object moves, no work is done. A: Regardless of the weight of the box, the man does no work on it as he holds it while walking across the room.
Q. What is the basis in choosing a situation where work is done?
Work is done when a force that is applied to an object moves that object. The work is calculated by multiplying the force by the amount of movement of an object (W = F * d). A force of 10 newtons, that moves an object 3 meters, does 30 n-m of work.
Table of Contents
- Q. What is the basis in choosing a situation where work is done?
- Q. Is carrying something considered work?
- Q. Why is the work done equal to zero when a person is simply carrying a bag while walking forward?
- Q. What is the work done by a porter carrying a suitcase on his head?
- Q. Why is no work done against the force of gravity when you hold a suitcase above your head?
- Q. Why is there zero work done when you carry your backpack down the hallway?
Q. Is carrying something considered work?
If there is no motion in the direction of the force, then no work is done by that force. Yet you certainly feel like you are doing work if you carry a heavy box. It changes the direction of the motion, but it does no work on the object.
Q. Why is the work done equal to zero when a person is simply carrying a bag while walking forward?
If you are moving forward at a constant speed then the work on the case is zero. There is no acceleration so there is no force and hence no work. This is the technically correct physics, even though it doesn’t feel like you’re not doing any extra work when you’re carrying it.
Q. What is the work done by a porter carrying a suitcase on his head?
Because person moves horizontal and force of gravity is vertical. So work done is Zero.
Q. Why is no work done against the force of gravity when you hold a suitcase above your head?
these muscles have fibers which have have streached themselves ,which requires energy, Similarly when we hold something above our head we r doing the same thing, resisting that collapsing tendency , which causes elongment in the muscles which requires energy.
Q. Why is there zero work done when you carry your backpack down the hallway?
Work = Force * displacement times the cosine of the angle between the two. If you lift an object straight up, the movement is vertical and the force is vertical and equal to the weight of the object. But the displacement is at right angles to the force, so no work is done by the wagon wheels.
