What happens to 's' if mass changes in this situation

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In summary, the question discusses the effect of changing the mass of two 1kg blocks that are launched down a ramp using a spring. It is mentioned that the blocks are fused together and there is friction between the block and the ramp. The question asks if changing the mass of the blocks would change the displacement of the system, and the answer is yes. When the mass increases, the net force applied to the block also increases, resulting in a shorter displacement. The increase in mass also affects the gravitational potential energy, but it does not have a direct effect on the displacement. Therefore, increasing the mass of the block will decrease the overall displacement of the system.
  • #1
Alice Saka
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Homework Statement


A spring is used to launch a two 1kg blocks down a ramp from the top. One of the block is stack (fused) on top of the other.
If the mass of the blocks were to change, i.e. double (making it 2kg blocks). does this change the displacement of this system? This system also has friction coming from the contact between the block and the ramp.

Due to confusion, new way to read it:
Basically the block is going down the ramp via a spring launching it. The block and ramp have friction between them. After the block is launched, it will have a displacement due to the work done by the spring and (I assume) gravitation potential energy.
Now we swap the blocks out for another heavier one and repeat this procedure. Would the increase of mass have us get a different displacement than using the lighter block.

Homework Equations


?

The Attempt at a Solution


I was thinking F=ma and that by increasing the mass of the object, the Net Force should increase as well. Therefore the displacement should also increase as there is more force on the blocks. I've also thought about the gravitational potential energy and that it will also increase the displacement if the mass was to change due to more stored energy.
 
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  • #2
Which displacement?
Is there a sketch?

Alice Saka said:
I was thinking F=ma and that by increasing the mass of the object, the Net Force should increase as well.
That depends on the possible change of the acceleration, but currently I have no idea what is moving where why,
 
  • #3
mfb said:
Which displacement?
Is there a sketch?

That depends on the possible change of the acceleration, but currently I have no idea what is moving where why,

No sketch. This is why I'm confused too.
Basically the block is going down the ramp via a spring launching it. The block and ramp have friction between them. After the block is launched, it will have a displacement due to the work done by the spring and (I assume) gravitation potential energy.
Now we swap the blocks out for another heavier one and repeat this procedure. Would the increase of mass have us get a different displacement than using the lighter block.
 
  • #4
Is this the exact and full problem statement? Then it is too ambiguous.
Also, where is the point in having two masses if they are fused together.

You can compare how far the blocks will slide down the ramp, assuming the ramp does not move.
 
  • #5
mfb said:
Is this the exact and full problem statement? Then it is too ambiguous.
Also, where is the point in having two masses if they are fused together.

You can compare how far the blocks will slide down the ramp, assuming the ramp does not move.
This is a modified version of the problem statement due to the original being more confusing because this was given by a student teacher whose English isn't her first language.
I think saying that the two blocks being fused together might have been a mistake and she meant one block.

If you want me to keep modifying this question to find out what you're looking for,
If you were to change the mass of the block, how would this affect the displacement on the block?

Also I realized F=ma can't happen due to the spring, so the net force applied to the block doesn't change as the force given by the spring stays the same (1/2*k*x2)
If the block was being pushed horizontal, I can say for certain that the displacement goes down if mass goes up. But I don't know if that is also true for the block going down the ramp due to gravitational potential energy.
 
  • #6
Alice Saka said:
This is a modified version of the problem statement due to the original being more confusing because this was given by a student teacher whose English isn't her first language.
I'm not sure if that helps, every translation step can have errors.

F=ma is a fundamental law - it does happen. That does not mean you can use it everywhere for every question because often you do not know F, m or a.

1/2 k x^2 is not the force, it is a different (and useful) quantity.
 
  • #7
I feel bad for wasting your time with this stupid question now.
Lets just end it here, but I'll need confirmation on my attempt.

My attempt:
Potential Energy in the spring stays the same and exerts the same amount of energy on the block. However the work done on the block is different. Since the block is heavier, the amount of energy exerted on the heavier block does not push it down the ramp as far as it did for the lighter block.
If mass increases, the displacement goes down (if we were to only look at the spring part).

Now for Gravitational Potential Energy.
Potential Energy (PE) is mass*gravity*height (PE = mgh). If mass were to increase, then the overall PE would increase as well. Even though PE increases, it doesn't increase the displacement of the block as it is proportional (I think).

Therefore, increasing the mass of the block in system will decrease the overall displacement.
 
  • #8
Alice Saka said:
Potential Energy (PE) is mass*gravity*height (PE = mgh). If mass were to increase, then the overall PE would increase as well. Even though PE increases, it doesn't increase the displacement of the block as it is proportional (I think).
Proportional to what?
Alice Saka said:
Therefore, increasing the mass of the block in system will decrease the overall displacement.
Right. It has the same effect as weakening the spring where that result is obvious.
 

1. What is the relationship between 's' and mass?

The relationship between 's' and mass is that 's' represents the distance between two objects, while mass represents the amount of matter an object contains. In most situations, the distance between two objects will remain constant regardless of changes in mass.

2. Will 's' change if mass changes?

In situations where the distance between two objects is directly affected by the mass of one or both objects, 's' will change if mass changes. This is known as the gravitational force and is described by Newton's Law of Universal Gravitation.

3. How does 's' change if mass changes?

If the mass of one or both objects increases, the force of gravity between them will also increase, causing the distance between the objects to decrease and 's' to become smaller. Conversely, if the mass decreases, the distance between the objects will increase and 's' will become larger.

4. Can 's' remain constant even if mass changes?

Yes, in situations where the distance between two objects is not affected by mass, 's' can remain constant even if mass changes. For example, in an elastic collision between two objects, the total momentum and kinetic energy will remain constant, thus keeping the distance between the objects constant as well.

5. What happens to 's' if the mass of one object is significantly larger than the other?

If one object has a much larger mass than the other, the force of gravity between them will be much stronger, causing the distance between the objects to decrease and 's' to become smaller. This is why small objects orbit larger objects, as the force of gravity between them is strong enough to keep them in a relatively constant distance.

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