(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is a problem off of http://www.physics247.com/physics-homework-help/pulley.php It is question number 6 but with an additional part and slight modification by my teacher. I will copy and paste it here but it may be best to view the link for the diagram.

Two blocks, one 0.8 kg and the other 2.0 kg are connected by a massless string over a frictionless pulley. The coefficient of kinetic friction is 0.14, and the downward ramp angle is 30 degrees (NOT 60 degrees as shown in the diagram).

a) Determine the acceleration of the blocks.

b) Calculate the tension of the string.

c) If the string broke, for what minimum value of the coefficient of static friction would the 2kg block not begin to slide?

m1 = 0.8kg

m2 = 2.0kg

uk = 0.14

2. Relevant equations

Fnet = ma

Ff = umg

Fg = mg

Fn = Fg

3. The attempt at a solution

I did a FBD and came up with this equation

Fnet = Fgx2.0 - Ff2.8 + Fg0.8 + Fgy2.0 - Fn0.8 I'm unsure if this is correct

Which meant 2.8a = 2gsin60 - u2.8g + 0.8g + 2g - 0.8g

But now i'm not sure what to do because my forces in the y direction dont equal zero.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Help with Pulley Problem

**Physics Forums | Science Articles, Homework Help, Discussion**