All Questions
15
questions
4
votes
6
answers
1k
views
Does work-energy theorem account for thermal energy?
Suppose a box (which I assume to be a rigid body) with an initial velocity that starts to slide on a level surface with friction. Imagine this experiment is done in vacuum, so there is no air drag or ...
4
votes
1
answer
1k
views
Is work done by the internal forces independent of the frame of reference?
This question is about work done being dependent on the frame of reference, which is, obviously the net work done.
I ask what is the reason for the work done by internal forces to be independent of ...
2
votes
1
answer
93
views
Conservation of energy with friction on a pool ball
I have a problem where I am given the mass $m$, radius $r$ and friction $\mu$ between a pool ball and table. The ball is not initially moving but at $t=0$ is struck by an impulse
$$p=\int_{-\epsilon}^...
2
votes
2
answers
314
views
Why frictional force does no work on the car?
Question statement from David Morin's Classical Mechanics :
The friction force from
the ground on the tires is what causes the car to slow down. But this force
does no work on the car, because the ...
1
vote
4
answers
1k
views
Sign of work done by friction
In Goldstein's classical mechanics (3rd ed.) we read:
"The independence of W12 on
the particular path implies that the work done around such a closed circuit is zero,i.e.
$$\oint \textbf{F}.d\...
1
vote
1
answer
35
views
If a cylinder skids what can we say about the work of friction on it
A cylinder skids on a rough horizontal plane and we know that a frictional force will act on it.
What can we say about the work done by friction?
I believe that the frictional force is forward, the ...
1
vote
2
answers
440
views
Why is the work done by friction zero when body is rolling? [duplicate]
Why is the work done by friction zero when body is rolling? Does it mean no energy is dissipated by friction.
1
vote
0
answers
1k
views
Work done by rolling vs skidding friction force
Two identical bicycles having equal weight riders are traveling along a level road adjacent to each other with the same non-zero velocity. Bike A, (the "skidder"), applies the rear brake strongly ...
0
votes
2
answers
615
views
Work done by friction over closed path
I am stuck thinking about work done by non-conservative forces. It is path dependent.
Let us consider an example.
A truck starts from rest and a block is kept on it. It accelerates for some time and ...
0
votes
1
answer
28
views
Work Done by kinetic friction in Circular Motion
We know when an object is moving in a circular motion on a rough horizontal surface, direction of kinetic friction is constantly. Thus, fto calculate the work doen by friction, we need to use ...
0
votes
2
answers
39
views
On source of heat energy dissipation in a system
Suppose we have a block of mass m which was at rest on a rough floor and is now given an impulse towards a wall.It is given that the collision with wall is perfectly elastic and no energy is lost in ...
0
votes
1
answer
54
views
About the work of the friction force [closed]
This will surely be a stupid question, but it bugs me.
Let's consider an inclined plane with friction.
We all know that the friction force is given by
$$f = \mu N$$
Where $N = mg\cos\theta$, the ...
0
votes
1
answer
263
views
Taylor Example 4.8. Is my reasoning sound? [closed]
This problem has been giving me all sorts of fits. For one, Taylor states that because the frictional force and normal force are forces of constraint, they produce no work. I'm trying to figure out ...
0
votes
2
answers
8k
views
Energy dissipated by friction vs Work done by friction
Is energy dissipated by friction the same as work done by friction where the equation is W(friction) = Ff * d cos theta .
However, since work is the transfer of energy and not energy itself then is ...
0
votes
1
answer
50
views
Work of friction along a circular path using dot product
Good day guys, I was working on circular motion and was wondering about the following:
I have seen that the work done by friction along a circular path is given by
$$W = F_fS$$
I was wondering if it ...