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Difference between energy and force?

by syano
Tags: difference, energy, force
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syano
#1
Oct17-03, 01:00 PM
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What is difference between energy and force? Is energy just a measurement of a force?

Thanks,

S
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mathman
#2
Oct17-03, 02:07 PM
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Simple example: Holding a rope taut is using force. Pulling something with rope is using energy.
enigma
#3
Oct17-03, 03:14 PM
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Energy is a 'property' which you have when a force is applied over a certain distance. It's sort of counting up all the force which has acted on you, and giving a number you can use to make calculations simpler.

Fuego
#4
Oct17-03, 03:26 PM
P: 43
Difference between energy and force?

energy is sort of the potential to exert a force.

more accurately, energy is the potential to do work, but work is a function of force.

forces change the way things move. to make something move, change direction or stop moving, you need to exert a force on it. but you cannot exert a force unless you have the energy to do so.

when you move your mouse, your hand exerts a force on the mouse to move it. the energy required to exert that force comes from the energy stored in your muscles.

another example: think about bowling a ball at some skittles. when the ball is rolling, it has energy (kinetic energy), when it hits the skittles, it uses up that energy to exert a force on the skittles. the force knocks the skittles over. the movement of the ball gives it the energy to exert that force.
krab
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Oct17-03, 03:55 PM
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Originally posted by syano
What is difference between energy and force? Is energy just a measurement of a force?
A big difference between the two is that force can be changed to much larger or smaller values by simple devices such as levers, screws, etc. But energy is a conserved quantity. So a given quantity of energy can be expended by applying a relatively large force over short distance, or smaller force over longer distance.
HallsofIvy
#6
Oct17-03, 08:50 PM
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Also important: there is a "conservation of energy" law. There is no "conservation of force". In order to lift an object with weight 1 Newton a height of 1 meter, I MUST do 1Newton* 1 meter= 1 Joule of work. But if I use an inclined plane instead of lifting it straight up, I can reduce the force necessary.


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