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highschoolstudent454

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**Mentor note: Moved from a technical section, so is missing the homework template.**

A Body of mass 1kg moves with a uniform velocity of magnitude 12m/s, a resistance of force of magnitude 6x^2 (newton) where x is the displacement (meter) which the body travels under the action of the resistance acts on it.

1) Find the work done by the resistance until x=4

2) Find the velocity of the body and its kinetic energy at x=2

A Body of mass 1kg moves with a uniform velocity of magnitude 12m/s, a resistance of force of magnitude 6x^2 (newton) where x is the displacement (meter) which the body travels under the action of the resistance acts on it.

1) Find the work done by the resistance until x=4

2) Find the velocity of the body and its kinetic energy at x=2

I have no problem in solving the question. However, I have some difficulty in describing motion over the change of x. I got the kinetic energy to be T = 72 - 2x^3 (after integrating with respect to x). Does this mean that the body will stop at x = 36^(1/3) < 4 as all initial kinetic energy will be consumed or will the body move in the opposite direction in the direction of the acting resistance?

**in other words**, w

*ill the body continue to move in the opposite direction or stop, and thus the first requirement would be meaningless?*

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