Hi!

Can someone help me understand my mistake???

18km/h=5m/s

m1v1 + m2v2 = (m1+2)vf = pf

20 * 5 + 5 * 0 = pf

100 kg * m/s= pf

25 kg * 5 m/s = 125 kg m/s

(m1 + m2) * (v1 + v2)

Thank you!

I might be over thinking this question, I donâ€™t understand why pf=vi * (m1+m2) with vi = vf

I was using the equation for inelastic collisions, and we should be loosing kinetic energy which is verified by

100=25vf

4= vf < vi so Ecf < Eci

Could someone help me understand? Thank you!

Its not technically an inelastic â€ścollisionâ€ť because she is already on the sled - its a weird question. It seems like they just want the combined mass x velocity.

The part they want you to mess up is the conversion.

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