These are two questions from an assignment which I just don't get. I'm in grade 12. I just want to be pointed in the direction, not given the answer. I wanna make sure I know this for the test, my teachers hard :((adsbygoogle = window.adsbygoogle || []).push({});

1) A 1.00kg mass and a 2.00kg mass are set gently on a platform mounted on an ideal spring of force constant 40.0N/m. The 2.00kg mass is suddenly removed. How high above this starting position does the 1.00kg reach?

I was thinking of determining the energy at equilibrium, because Ee = 0 and Ek = max at that point...but it would become zero, would it not? or, could i equal Ek1 + Ee1 = Ee2 + Ek2? I dunno...

2) A ball of mass 0.25kg is thrown vertically upward from the roof of a building 18m high with a speed of 16m/s, and just misses the building on the way down

a) To what vertical height above Earth does the ball rise?

b) With what vertical velocity does the ball hit the ground?

dy = v1t + -.5at^2? But I don't know time, or the vertical distance...I dunno where to begin, I used to be able to do this...but slipped my mind completly.

Thanks for any help :D

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# Homework Help: Projectile Motion and Spring Question

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