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tica86
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An object of mass 0.550 kg is lifted from the floor to a height of 3.50m at a constant speed.
Can someone please check my answers, thanks!
1) How much work is done by the lifting force?
(0.550kg)(9.80m/s^2)(3.50)=18.9J
2) How much work is done by the Earth on the object?
I was told it was 0 but I think it's -18.9J
because W=-mgh
3) What is the net work done on the object?
Again I was told it was 18.9 J which I don't think it's correct
I think it's 0
4) What is the change in kinetic energy of the object?
0
5) What is the kinetic energy just before it hits the floor?
18.9J
6) What is its velocity?
This one I'm a little confused with, is it
(1/2)mv^2=18.9J
v^2=1/2m-18.9J
Also, I have no idea how to try and solve the following:
A force acts on an object of mass 0.425 kg. The force varies with position. Find the work done by the force in moving the object from 0.40m to 1.20m.
Can someone please check my answers, thanks!
1) How much work is done by the lifting force?
(0.550kg)(9.80m/s^2)(3.50)=18.9J
2) How much work is done by the Earth on the object?
I was told it was 0 but I think it's -18.9J
because W=-mgh
3) What is the net work done on the object?
Again I was told it was 18.9 J which I don't think it's correct
I think it's 0
4) What is the change in kinetic energy of the object?
0
5) What is the kinetic energy just before it hits the floor?
18.9J
6) What is its velocity?
This one I'm a little confused with, is it
(1/2)mv^2=18.9J
v^2=1/2m-18.9J
Also, I have no idea how to try and solve the following:
A force acts on an object of mass 0.425 kg. The force varies with position. Find the work done by the force in moving the object from 0.40m to 1.20m.