Finding the mass of a hockey puck - inertia

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To find the mass of a hockey puck given its initial and final velocities and the impulse applied, the momentum equation m(vf) - m(vi) can be utilized, where j (impulse) equals the change in momentum. The impulse provided is 4.5 kg*m/s, and since the puck moves in the opposite direction with the same speed, the change in momentum can be set equal to the impulse. The discussion highlights confusion over calculating mass due to the absence of a known force or maximum force (fMax). Participants express a need for clarification on using the impulse-momentum relationship effectively. Understanding these concepts is crucial for solving the problem accurately.
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Finding the mass of a hockey puck - inertia!

An ice hockey puck slides along the ice at 12m/s. A hockey stick delivers an impulse of 4.5 kg * m/s, causing the puck to move off in the opposite direction with the same speed. What is the mass of the puck. Friction and drag are negligible.

Any Ideas? I am completely lost.

Thanks!
 
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Units...

Thanks!

Yes my units are correct. I was skimming over my notes from class and I believe we have to use the ∆px=jx=area under the curve equation

to find the ball's momentum:

m(vf)x-m(vi)x but then I don't have "m" this whole thing is equal to jx

and then the area under the curve

jx=fmax • ∆time

but I have jx and the velocities, but not the mass or the fMax
 
crewrules101 said:
Thanks!

Yes my units are correct. I was skimming over my notes from class and I believe we have to use the ∆px=jx=area under the curve equation

to find the ball's momentum:

m(vf)x-m(vi)x but then I don't have "m" this whole thing is equal to jx

and then the area under the curve

jx=fmax • ∆time

but I have jx and the velocities, but not the mass or the fMax
oh sorry, you're actually ahead of me :-p hopefully someone will be able to help you tonight.
 
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Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

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