Homework help: Work and Energy: Spring

[Syeda]

Homework Statement

A .5 kg loaded toy (spring k=8000 n/m) loaded toy is compressed .05 m and fired on a flat surface
a) Find the new speed it was released with
b) If it approaches a hill find the maximum height it can climb

Homework Equations

KE=1/2kx²
KE=1/2mv²
PE=1/2kx^2

The Attempt at a Solution

a) KE= 1/2(8000N/m)(.05m)²
KE=200J

KE=1/2mv²
200J=1/2(.5kg) v²
v= 28.284 m/s

b) PE=1/2kx^2
PE=10J
PE=mgh
10=.5kg(9.8m/s²)x
2.04m=h

 

[gneill]

In part (a), check your calculation of spring potential energy. Interestingly, you used the correct value for energy in part (b).

 

[Syeda]

In part (a), check your calculation of spring potential energy. Interestingly, you used the correct value for energy in part (b).

Thank you for catching my mistake! I forgot to square the values so this is what I got for part a now:
10=1/2(.5)v²
v=6.32m/s

 

[gneill]

That looks better. I think you're all good now.