Energy and friction -- Can the block make it all the way up the ramp?

In summary: Exactly! I tried it in several ways and got the x of the Elastic Potential Energy formula (U = kx ^ 2/2). Today the professor said he was wrong and added a piece of information to the question. He forgot to say that x = 20cmFirst, what are the dimensions of the problem? ##\ ##To get started, don't make things too difficult. Thank you for your help!I am dividing the problem into two parts. And I will follow your line of reasoning. Thank you very much!First, what are the dimensions of the problem?
  • #1
LulyPop
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Homework Statement
Can the block go up the ramp completely even with the friction of the ramp?
Relevant Equations
∆E = ∆K - ∆U
∆U = m* g* h
Wm = -1/2 kx²
Wfat = µc * m *g *d
Quest 4.jpg
 
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  • #3
There will be an impact event when the block reaches lower end of the ramp. Do you wish to correctly consider that and the associated energy loss, or did you intend this to be done assuming energy is conserved until the friction work on the ramp occurs?
 
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  • #4
Dr.D said:
There will be an impact event when the block reaches lower end of the ramp. Do you wish to correctly consider that and the associated energy loss, or did you intend this to be done assuming energy is conserved until the friction work on the ramp occurs?
Hi!
I didn't think about the impact with the start of the ramp. I considered that until we go up the ramp we have only conservative forces. When going up, as we have the kinetic frictional force, which is a non-conservative force, I think it reduces the speed of the block and transforms the kinetic energy of the block to another form of energy.
 
  • #5
LulyPop said:
Hi!
I didn't think about the impact with the start of the ramp. I considered that until we go up the ramp we have only conservative forces. When going up, as we have the kinetic frictional force, which is a non-conservative force, I think it reduces the speed of the block and transforms the kinetic energy of the block to another form of energy.
Yeah, I think this is a simple enough problem (as shown) that you don't need to consider the abrupt transition impact. Just go ahead and solve it using the friction coefficient (and associated force) changing the PE-KE balance. Please show us your work. Thank you.
 
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  • #6
berkeman said:
Yeah, I think this is a simple enough problem (as shown) that you don't need to consider the abrupt transition impact. Just go ahead and solve it using the friction coefficient (and associated force) changing the PE-KE balance. Please show us your work. Thank you.
Thank you for the tips. I'll try again!
 
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  • #7
It is a pretty good assume conservation of energy as the block approaches the ramp. However, the impact at the sudden direction change will reduce the kinetic energy available for the climb.
 
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  • #8
Don't we need some initial condition ? I feel it makes a difference if the spring is compressed by 2 m instead of 0.5 m ... :rolleyes:
Or is that part of the exercise ?

##\ ##
 
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  • #9
BvU said:
Don't we need some initial condition ? I feel it makes a difference if the spring is compressed by 2 m instead of 0.5 m ... :rolleyes:
Or is that part of the exercise ?

##\ ##
Exactly! I tried it in several ways and got the x of the Elastic Potential Energy formula (U = kx ^ 2/2). Today the professor said he was wrong and added a piece of information to the question. He forgot to say that x = 20cm
 
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  • #10
Dr.D said:
It is a pretty good assume conservation of energy as the block approaches the ramp. However, the impact at the sudden direction change will reduce the kinetic energy available for the climb.
I am dividing the problem into two parts. And I will follow your line of reasoning. Thank you very much!
 
  • #11
LulyPop said:
I am dividing the problem into two parts. And I will follow your line of reasoning. Thank you very much!
To get started, don't make things too difficult.
You have initial spring compression energy ##\rightarrow## initial kinetic energy ##\rightarrow## maximum ##\Delta h##.
So the yes/no can be resolved. Since you know nothing about the sudden direction change, the best you can do is assume that speed changes direction, not magnitude at that point.

##\ ##
 

1. What is energy and how does it relate to friction?

Energy is the ability to do work. Friction is a force that opposes motion and can cause energy to be lost as heat. Therefore, energy and friction are closely related as friction can decrease the amount of energy available for an object to move.

2. How does the angle of the ramp affect the block's ability to make it all the way up?

The angle of the ramp can affect the block's ability to make it all the way up by changing the amount of work needed to overcome friction. A steeper ramp will require more energy to overcome friction, while a shallower ramp will require less energy.

3. Is it possible for the block to make it all the way up the ramp without any friction?

No, it is not possible for the block to make it all the way up the ramp without any friction. Friction is necessary to provide the necessary force for the block to move up the ramp. Without friction, the block would simply slide down the ramp.

4. How can we decrease the effects of friction on the block?

We can decrease the effects of friction on the block by using a smoother surface for the ramp, such as a polished or lubricated surface. Additionally, reducing the weight of the block or using a lighter material can also decrease the effects of friction.

5. Can we completely eliminate friction in this scenario?

No, we cannot completely eliminate friction in this scenario. Friction is a natural force that is present in all interactions between surfaces. While we can reduce its effects, it is impossible to completely eliminate friction.

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