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# Kinetic energy graph watch

1. For an object has a constant force of 10N applied to it (mass = 1kg). This implies that the acceleration is constant and = 10ms^-2.
This means that the rate of increase in velocity is constant, hence a velocity displacement graph is a straight line increasing" / " .
SO If a question as draw the graph of kinetic energy against displacement....

How come these methods have different outcomes?
work done = kinetic energy so F X d = KE which gives 10 * 10 = 100
And so a graph of KE against d would be a straight line "-" form o to 100 J because the area of the force/displacement increases at a constant rate.

However, if you look at the equation of KE=1/2 mv^2 then that would surely suggest KE is proportional to V^2 so the graph would be a curve as velocity is increasing due to the acceleration?

e.g. http://slideplayer.com/slide/1671985...aight+line.jpg

How should the graph look (a straight line 0 to 100 as KE=F*d) or a line curving up form 0 to 100 (As KE is proportional to velocity squared)?
2. (Original post by splitter2017)
For an object has a constant force of 10N applied to it (mass = 1kg). This implies that the acceleration is constant and = 10ms^-2.
This means that the rate of increase in velocity is constant, hence a velocity displacement graph is a straight line increasing" / " .
SO If a question as draw the graph of kinetic energy against displacement....

How come these methods have different outcomes?
work done = kinetic energy so F X d = KE which gives 10 * 10 = 100
And so a graph of KE against d would be a straight line "-" form o to 100 J because the area of the force/displacement increases at a constant rate.

However, if you look at the equation of KE=1/2 mv^2 then that would surely suggest KE is proportional to V^2 so the graph would be a curve as velocity is increasing due to the acceleration?

e.g. http://slideplayer.com/slide/1671985...aight+line.jpg

How should the graph look (a straight line 0 to 100 as KE=F*d) or a line curving up form 0 to 100 (As KE is proportional to velocity squared)?
Velocity is not the same as distance moved in direction of force, u seem to be confusing two different situations here.

Please ask any questions u have so i can help with ur understanding.
3. (Original post by Shaanv)
Velocity is not the same as distance moved in direction of force, u seem to be confusing two different situations here.

Please ask any questions u have so i can help with ur understanding.
OK, I have written out what I am trying to understand with the two methods named scenario 1 and scenario 2. I hope this helps describe what I am stuck with.
My abbreviation KE represents kinetic energy.

I am simply trying to sketch how kinetic energy would change over the journey i.e. kinetic energy against displacement.

4. (Original post by splitter2017)
OK, I have written out what I am trying to understand with the two methods named scenario 1 and scenario 2. I hope this helps describe what I am stuck with.
My abbreviation KE represents kinetic energy.

I am simply trying to sketch how kinetic energy would change over the journey i.e. kinetic energy against displacement.

Scenario 2 would be correct. You're also correct in saying that KE = Fd but I don't quite understand how you've got a straight line graph from that equation.

The only graph you can assume from KE=Fd would be one plotted with force against distance where the area underneath the graph equals KE. And it is not a straight line graph through the origin as the same force is applied constantly over the distance.
5. (Original post by G.Y)
Scenario 2 would be correct. You're also correct in saying that KE = Fd but I don't quite understand how you've got a straight line graph from that equation.

The only graph you can assume from KE=Fd would be one plotted with force against distance where the area underneath the graph equals KE. And it is not a straight line graph through the origin as the same force is applied constantly over the distance.
Lol wait. If force is constant and KE=Fd then the gradient of a KE against d graph would have to be constant meaning it cannot be curved.
6. (Original post by splitter2017)
OK, I have written out what I am trying to understand with the two methods named scenario 1 and scenario 2. I hope this helps describe what I am stuck with.
My abbreviation KE represents kinetic energy.

I am simply trying to sketch how kinetic energy would change over the journey i.e. kinetic energy against displacement.

Maybe the following equation can help:
v2 = u2 + 2as

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