1. same direction. Physics 

 

The work done by the gravitational force is negative, as the force and displacement are in opposite directions.

 

Question 4: A box of mass 1 kg is pulled on a horizontal surface of length 1 meter by a force of 8 newtons. It is then raised vertically to a height of 2 meters at a constant speed. What is the net work done?

 

Solution:

 

The work done on the horizontal surface is given by:

 

Work done = Force x Displacement x cos(theta)

 

= 8 newtons x 1 meter x cos(0 degrees)

 

= 8 joules

 

The work done in raising the box vertically is given by:

 

Work done = Force x Displacement x cos(theta)

 

= 1 kg x 9.8 m/s^2 x 2 meters x cos(180 degrees)

 

= -19.6 joules

 

The net work done is the sum of the work done on the horizontal surface and the work done in raising the box vertically:

 

Net work done = 8 joules + (-19.6 joules) = -11.6 joules

A 230 kg crate hangs from the end of the rope of length L=12.0 m. you push horizontally on the crate with a varying force F to move it distance d= 4.00m to the side a) what is the magnitude of F when the crate is in this final position? During the crate's displacement, what are (b) the total work done on it, (c) the work done by the gravitational force on the crate, and (d) the work done by the pull on the crate from the rope? (e)Knowing that crate is motionless before and after its displacement, use the answer to (b), (c) and (d) to find the work your force F does on the crate (f) why is the work of your force not equal to the product of the horizontal displacement and the answer to (a)?

A 230 kg crate hangs from the end of a rope of length L=12m. You push horizontally on the crate with a varying force F to move it distance d=4m to the side. a) What is the magnitude of the F when the crate is in this final position? during the crate's displacement, what are b) The total work done on it? c) The work done by the gravitational force on the crate? d) The work done by the pull on the crate from the rope? e) Knowing that the crate is motionless before and after its displacement, use the answers to b), c), and d) to find the work your force F does on the crate? f) Why is the work of your force not equal to the product of the horizontal displacement and the answer a)?