Physics question
- Thread starter Crusher
- Start date
1-Yes
2- Friction, unless the surfaces we're talking about are super-de-frictioned, or you're talking about some super-sci-fi frictionless materials.
3- Dunno.. beyond me.. i'm sure it's in a book somewhere or the web.. check Wikipedia.
It should keep moving as kinetic friction is less than the maximum static friction.
The kinetic friction coefficient can be solved using a free body diagram and setting up Newtons 2nd law for x and y directions. I get:
kinetic friction coefficient = [ gsin(angle) - a ]/gcos(angle)
I can outline the steps if you want.
The kinetic friction coefficient can be solved using a free body diagram and setting up Newtons 2nd law for x and y directions. I get:
kinetic friction coefficient = [ gsin(angle) - a ]/gcos(angle)
I can outline the steps if you want.
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If you angle it enough to it can start moving, so gravity pulling it forward (from the point of view of the plane) is strong enough to overcome friction, why would it decide to stop again later on? The friction it has while it's still is usually greater or equal to the friction it has when moving too so if the former can be overcome, how could the latter stop the object then?
Unless you're dealing with weird materials where dynamic friction is somehow higher than static friction. But I don't think an object would start moving then until the gravitational pull is higher than the stronger friction so again, I see no reason for it to stop.
Unless the angle or the friction changes somewhere down the road, of course.
I'm not studying this though. This is all just school knowledge, fed through my stupidity filter and perforated with oblivion... So don't quote me.
Static friction (ie when the object is resting on the surface) is always higher (or equal to) than kinetic friction (ie when the object is moving). That's why it doesn't stop once it starts to move.
friction coefficient = force that is required to move the object / N (which is mg)
friction coefficient = force that is required to move the object / N (which is mg)
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The static friction force can be lower than the kinetic friction force. It's that the maximum static force is greater than the kinetic friction force.
So say you tilt the plane until you're right at the max friction force. Right at that angle the force of gravity and the static friction balance out to zero. Tilt the plane up just a little bit more, and the object starts sliding down, but kinetic friction is less than the static friction, which is less than the force of gravity. So it keeps on sliding down, accelerating to.
So say you tilt the plane until you're right at the max friction force. Right at that angle the force of gravity and the static friction balance out to zero. Tilt the plane up just a little bit more, and the object starts sliding down, but kinetic friction is less than the static friction, which is less than the force of gravity. So it keeps on sliding down, accelerating to.
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I was explaining myself from my first post, since I really didn't do a good job of it there
So yea, pretty much to Crusher
So yea, pretty much to Crusher
If two IS2s` travelling at the speed of light hit each other head on, at the same time as firing their main guns, what would happen?
Piece of cake = Big Bang.
This thread needed a little kick-start, I believe I achieved the desired effect.
Aren't we forgetting potential energy?
(Its been a century or two and I can't find my Engineer's Handbook. I think my son has it with him at school...
)
(Its been a century or two and I can't find my Engineer's Handbook. I think my son has it with him at school...
)
Aren't we forgetting potential energy?
(Its been a century or two and I can't find my Engineer's Handbook. I think my son has it with him at school...
Well, the potential energy is E = mgh in this case
FREE BODY DIAGRAM!
Use the angle of the inclined plane to calculate the force of gravity acting on the block, parallel to the inclined plan. It should give you an acceleration. Compare the actual acceleration to the acceleration you just calculated. The difference times the mass gives you the force of kinetic friction (in the plane that the block is sliding)
Use the angle of the inclined plane to calculate the force of gravity acting on the block, parallel to the inclined plan. It should give you an acceleration. Compare the actual acceleration to the acceleration you just calculated. The difference times the mass gives you the force of kinetic friction (in the plane that the block is sliding)