Solving for the Distance of Fall for 4kg Block

[redhot209]

Homework Statement

A block of mass 3 kg is hung from a spring, causing it to stretch 6 cm at equilibrium, as shown below. The 3 kg block is then replaced by a 4 kg block, and the new block is released from the position shown below, at which point the spring is unstretched. How far will the 4 kg block fall before its direction is reversed? Hint: for the new block case, the total distance of fall is twice the amplitude of the oscillation. The acceleration of gravity is 9.8 m/s2

Homework Equations

My teacher give me this equation. Y2= Y1(M2/M1)

The Attempt at a Solution

Y2=6(3/4) = 8

 

[physics girl phd]

Homework Statement

A block of mass 3 kg is hung from a spring, causing it to stretch 6 cm at equilibrium, as shown below. The 3 kg block is then replaced by a 4 kg block, and the new block is released from the position shown below, at which point the spring is unstretched. How far will the 4 kg block fall before its direction is reversed? Hint: for the new block case, the total distance of fall is twice the amplitude of the oscillation. The acceleration of gravity is 9.8 m/s2

Homework Equations

My teacher give me this equation. Y2= Y1(M2/M1)

The Attempt at a Solution

Y2=6(3/4) = 8

Explain your reasoning. There's lots of fun physics in this problem... and you aren't discussing it! (Your answer also doesn't have units... and you don't seem to know where the equation comes from. I honestly don't either. I'd trace through things I do know, about stretch, energy stored, force...