Springs (Physics) Question

Hi, could someone please help me with this question:

A pop-up toy consists of a head and sucker of combined mass m=1.5kgm=1.5kg stuck to the top of a light spring of natural length l0=0.30m and spring constant k=250Nm^−1. The centre of mass of the system can be taken to be at the top of the spring. The spring is compressed to length l1=0.10m when the pop-up is stuck to the ground.

What height above the ground does the bottom of the unstretched spring jump to when it is smoothly released?

(edited 8 years ago)

Reply 1

DropTheOH-

Hey, I'm stuck on the very same question! Figure it out yet? I'm guessing you are also doing the prep work for the Cambridge physics experience day :smile:

Reply 2

LauraLovesOtters

Original post by DropTheOH-

Hey, I'm stuck on the very same question! Figure it out yet? I'm guessing you are also doing the prep work for the Cambridge physics experience day :smile:

Yes I am! No, I'm just going to leave it now and hope it doesn't matter that i've not finished all the questions.

Reply 3

Joinedup

have you tried conservation of energy?

seems you'd be able to calculate the PE stored in the compressed spring and equate it with the GPE of the toy at maximum altitude with the information provided.