Finding the Magnitude of Force without Time: A Rocket Pack Dilemma

AI Thread Summary
To find the magnitude of the force exerted by Pam's rocket pack, the work-energy principle can be applied, where work done equals the change in kinetic energy. Pam's initial kinetic energy is zero since she starts from rest, and her final kinetic energy can be calculated using the formula KE = 0.5 * m * v^2, resulting in 1406.25 J. The work done by the force over the distance of 22.0 m is equal to this kinetic energy, leading to the equation W = F * d. By rearranging this to solve for force (F = W/d), the correct force can be determined. The relationship between work and force is crucial in solving these types of problems.
amcoolio
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Hello all. Great site here. I have been working on this problem for a while now and I cannot figure out the magnitude of the force.

Pam, wearing a rocket pack, stands on frictionless ice. She has a mass of 45 kg. The rocket supplies a constant force for 22.0 m, and Pam acquires a speed of 62.5 m/s. Unless otherwise directed, assume that air resistance is negligible. What is the magnitude of the force? What is Pam's final Kinetic Energy?

How do you figure out the force when time is not a given? I have tried 441 N but it is wrong. (This is internet homework and I have used up 2 submissions. I have 8 submissions left.)
 
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How much kinetic energy does Pam have at the start, when she's motionless?

How much kinetic energy does Pam have at the end, when she's going 62.5 m/s?

How are work and force related?

- Warren
 
lol I am sooo stupid...I forgot about W=chgKE

thanks
 
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