(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

a 100g granite cube slides down a 40 degree frctionless ramp. at the bottom, just as it exits onto a horizontal table, it collides with a 200g steel cube at rest. how high above the table should the granite cube be released to give the stell cube a speed of 150cm/s

2. Relevant equations

Ek=1/2mv^2

Eg=mgy

maybe Ptot=ptot'

3. The attempt at a solution

first i tried the problem with the conservation of energy where the energy from the first block is transfered to the second (the Ek of 1st block is transfered to Ek second block). that didnt work. then i tried the conservation of momentum but you cant use it because you dont know if it is a perfectly elastic collision of the cubes stick together. you cannot assume anything, so i think i need to utilize the conservation of momentum, but its not giving me the right answer!!!! the answer should be 25.9cm and i keep getting 23cm. also, using the conservation of energy, the angle is irrelevant.

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# Homework Help: 2 cube collision inquiry

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