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
Messages
2
Reaction score
0
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.)
 
Physics news on Phys.org
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
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top