Energy of a block on a frictionless ramp

[geena_booboo]

Homework Statement

A 5.0 kg block is placed near the top of a frictionless ramp, which makes an angle of 30.0o degrees to the horizontal. A distance d = 1.3 m away from the block is an unstretched spring with k = 3000.0 N/m. The block slides down the ramp and compresses the spring. Find the maximum compression of the spring.

Homework Equations

The "solutions guide" is wanting me to use GPE=mgh (and I can substitute (1.3 + x) for h) and SPR=.5kx^2.

The Attempt at a Solution

I've tried setting them equal to each other, but then I get x as .137 and they say that's not correct.

 

[TSny]

GPE=mgh (and I can substitute (1.3 + x) for h)

Hello, welcome to PF!

Is h a distance measured along the surface of the inclined plane?

 

[cepheid]

Welcome to PF geena_booboo

Homework Statement

A 5.0 kg block is placed near the top of a frictionless ramp, which makes an angle of 30.0o degrees to the horizontal. A distance d = 1.3 m away from the block is an unstretched spring with k = 3000.0 N/m. The block slides down the ramp and compresses the spring. Find the maximum compression of the spring.

Homework Equations

The "solutions guide" is wanting me to use GPE=mgh (and I can substitute (1.3 + x) for h) and SPR=.5kx^2.

The Attempt at a Solution

I've tried setting them equal to each other, but then I get x as .137 and they say that's not correct.

Setting h = 1.3 + x is definitely not correct. You need to figure out change in vertical height of the block. This depends on how far along the ramp the block travels. It's not totally clear from the problem statement, but I think that the block is 1.3 m away from the spring along the ramp. If so, you need to use trigonometry to find the vertical height based on the distance that it travels along the ramp .

 

[geena_booboo]

I appologize, I meant that h=(1.3+x)sin(30).

 

[cepheid]

I appologize, I meant that h=(1.3+x)sin(30).

Okay, well it looks like calcuation error. Can you post your steps?