# Homework Help: Spring and friction assignment

1. Jun 8, 2007

### kar_04

another physics question..plz

Albertine sits ina reclining chair, in front of a large, compressed spring. The spring is compressed 5m from its equilibrium position, and a glass sits 19.8 m from her outstretched foot. Assuming that Albertine's mass is 60kg what is the coefficient of kinetic friction between the chair and the waxed floor?

U(kinetic) = F/N
N= 588
F=??
a=??

2. Jun 9, 2007

### chaoseverlasting

Assuming that she just touches the glass, $$0.5kx^2=\mu mgx$$ where x is 19.8 m, but you dont know k (spring const) which is reqd.