Work-Kinetic Energy question

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In summary, the conversation is discussing the calculation of maximum kinetic energy for a particle moving along the x-axis under the influence of a single force. The formula for the Work Kinetic Energy theorem is used to solve the problem, with the final step being to multiply 1/k by F0 to obtain the answer. The conversation ends with a thank you for the help.
  • #1
kiowaviator
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This question is whooping me. I know I have the calculus part right I just don't know where to go from here?

A particle moving along the x-axis is acted upon by a single force F = F0e^(–kx), where F0 and k are constants. The particle is released from rest at x = 0. It will attain a maximum kinetic energy of

F0/k
F0/e^(k)
kF0
1/2(kF0)^2
ke^(k)F0

So using the Work Kinetic Energy theorem
W=Kf-Ki since x=0 then Kf=W

W=integral(F = F0e^(–kx),x,0,xf)
taking F0 out, since its a constant, and integrating the exponential function I get
W=F0[-e^(-kxf)/k + 1/k]

now what?
 
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  • #2
When you evaluate the integral one of the terms is zero,

exp(-x) goes to zero as x goes to infinity?
 
  • #3
I did that, that's why the second term inside the brackets is 1/k, since e^(-k*0)=1.
 
  • #4
You've pretty much done it now. So you now have 1/k inside the bracket and f0 outside the bracket, so just multiply them together to get the answer.
 
  • #5
Ok, that makes sense. I was there I just couldn't see it. Thanks all.
 

What is work-kinetic energy theorem?

The work-kinetic energy theorem states that the net work done on an object is equal to the change in its kinetic energy. In other words, the work done by all forces acting on an object will result in a change in its speed.

What is the formula for work-kinetic energy theorem?

The formula for work-kinetic energy theorem is W = ΔKE = KEf - KEi, where W is the work done on the object, ΔKE is the change in kinetic energy, KEf is the final kinetic energy, and KEi is the initial kinetic energy.

How is work related to kinetic energy?

Work and kinetic energy are directly related. Work is the transfer of energy from one object to another, and in the case of work-kinetic energy theorem, this transfer results in a change in the object's kinetic energy. The more work done on an object, the greater its change in kinetic energy.

Can kinetic energy be negative?

No, kinetic energy cannot be negative. Kinetic energy is always a positive quantity, as it represents the energy an object possesses due to its motion. If an object is at rest, its kinetic energy is zero.

How does friction affect work-kinetic energy theorem?

Friction is a force that opposes motion and does negative work on an object. This means that friction decreases the amount of work done on an object and therefore decreases its change in kinetic energy. This is why it is important to consider friction when applying the work-kinetic energy theorem.

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