Does more energy equate to more force?

In summary, more energy means more force, but it's not the only variable. When you have more energy, you also have more momentum and this is what affects how far the nail goes into the wood.
  • #1
sgstudent
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3
Since energy is changed to work done, and the distance will be constant, the only variable is the force. So 100N compared to 50N will have double the force. So does it mean more energy more force?

Thanks for the help!
 
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  • #2
hi sgstudent! :smile:
sgstudent said:
So does it mean more energy more force?

i don't really follow what you're asking :confused:

energy doesn't cause force

for example, if we drop something then yes it gets more energy, but that's because a force (gravity) is working on it

what situation did you have in mind?​
 
  • #3
Something like, when I whack a hammer onto a nail. With more energy I whack the hammer will there be more force?

Since kinetic energy changes to work done, so work done equal force x distance. Since distance is greater, then there will be more force? Then again if the hammer hits with constant velocity then the hammer will have no energy, but when it 'imparts' that energy to the hammer then work done occurs?
 
  • #4
sgstudent said:
Something like, when I whack a hammer onto a nail. With more energy I whack the hammer will there be more force?

i don't know why you're calling that "energy"

your arm is using force to move the hammer, not energy

and the hammer is being supplied with momentum rather than energy …

it's the change in the hammer's momentum (when it is stopped by the nail) that gives momentum to the nail
 
  • #5
Sorry I'm taking O levels so I have not learned momentum yet. What I'm trying to say is: when I whack using a hammer into a nail, I have a certain amount of kinetic energy using the formula 1/2mv^2 then that energy is converted to work done to push the nail in. So with a greater kinetic energy there will be s greater work done right? And since the nail will move in the same distance, the force will be more when energy is more.

Is this right too? Thanks for the help!
 
  • #6
sgstudent said:
And since the nail will move in the same distance, the force will be more when energy is more.

that's what was puzzling me …

why will the nail move the same distance? :confused:

surely if you hit it harder, it wil go in further? :smile:​
 
  • #7
sgstudent said:
Since energy is changed to work done, and the distance will be constant, the only variable is the force. So 100N compared to 50N will have double the force. So does it mean more energy more force?

Thanks for the help!

ΔE = W = - FΔX

Yes double energy (ΔE → 2ΔE) means double work (W → 2W) and if distance is constant double force (F → 2F) being applied.
 
  • #8
Oh but if the nail doesn't go in as much then what would happen?Im really confused about the two concepts I understand what force is but I don't know the relationship between the them...
Could u explain this to me?

Thanks for the help!:)
 
  • #9
sgstudent said:
Sorry I'm taking O levels so I have not learned momentum yet. What I'm trying to say is: when I whack using a hammer into a nail, I have a certain amount of kinetic energy using the formula 1/2mv^2 then that energy is converted to work done to push the nail in. So with a greater kinetic energy there will be s greater work done right? And since the nail will move in the same distance, the force will be more when energy is more.

Is this right too? Thanks for the help!

Perhaps I can help clear up some misunderstandings. The hammer HAS energy and momentum when you are swinging it and are about to hit the nail. Energy is just a measure of the ability to do work. Upon impact the hammer exerts a force against the nail, and it is this force that pushes the nail in, not work or energy. However, the nail also pushes back equally, which is what causes the hammer to stop when it hits the nail.

Now, just because a hammer has more energy doesn't mean it has a higher force. If you hit the nail with a hammer, and then put it down and pick up another hammer which has twice the mass and swing it at the same speed it will still exert the same force as the first hammer. However, the 2nd hammer has twice momentum and energy as the 1st one and it will take more work (and energy) to swing it AND to stop it. Put simply, momentum is a measure of how hard it is to stop an object and is a product of the object mass times it's velocity, or p = mv. This means that it will take longer to slow down after it hits the nail, causing the nail to get hammered in further than with the first hammer.

But we can also get twice the momentum with the 1st hammer by swinging it twice as fast. HOWEVER, as Ke = 1/2mv^2 tells us, it takes 4 times as much energy to swing the hammer twice as fast. So to hit the nail in further we can either use a heavier hammer or swing the same hammer faster. The reason we don't walk around with huge hammers everywhere just tapping nails in is because it takes a lot of energy and effort to carry big hammers around compared to small hammers!

(I THINK that's all pretty much correct. Someone let me know if I've butchered physics somewhere)
 

1. Does an increase in energy always result in an increase in force?

Not necessarily. While energy and force are related, they are not directly proportional. The amount of force generated depends on factors such as the type of energy being used and the efficiency of the system.

2. Can energy and force be considered interchangeable?

No, energy and force are two distinct physical quantities. Energy is the ability to do work, while force is the push or pull that results in motion. However, energy can be converted into force and vice versa in certain situations.

3. Is it possible to have more force without using more energy?

Yes, there are other factors besides energy that can affect the magnitude of force, such as the mass of an object or the distance over which the force is applied. In some cases, a smaller amount of energy can result in a larger force if used efficiently.

4. How does the concept of energy relate to the concept of force?

Energy and force are closely related as they both play a role in the motion of objects. Energy is the source of force, and force is what causes objects to move. In simple terms, energy is the fuel for force.

5. Does more energy always mean more work can be done?

No, the amount of work that can be done depends on factors such as the type of energy being used and the efficiency of the system. Additionally, the type of work being done may require a different form of energy, so simply having more energy may not necessarily result in more work being done.

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