Homework Help: String Friction Question

1. Sep 24, 2007

ttk3

1. The problem statement, all variables and given/known data
What concepts am I missing?

A mass M is initially at rest on a horizontal surface, ms=0.30 and mk=0.20 . A horizontal string then pulls M with a tension T. Forces below are magnitudes.

Correct Incorrect M will accelerate if T exceeds ukN
Correct Incorrect N equals Mg
Correct Incorrect M will accelerate if T exceed usN
Correct Incorrect T equals usN if M remains at rest
Correct Incorrect If M does not accelerate, then T less than or equal to usN
Correct Incorrect The NET force on M (if M does not move) is ukN

2. Relevant equations

3. The attempt at a solution

correct by exceeding the kinetice friction the mass will accelerate
correct N and mg cancel on a level surface
correct it will move from rest
incorrect it could be lower than usN
correct
incorrect it would be true for ukn

2. Sep 24, 2007

learningphysics

I think you have everything right, except the first one...