I have to problems that I'm having trouble with today I just can't seem to get my head around a lot of these physics concept so I'm finally coming here Plz help me. I've tried to do these problems and I just don't know what I'm doing.(adsbygoogle = window.adsbygoogle || []).push({});

1.We have two masses hanging from a pulley of inertia mp and constant frictional force f. One mass is 21.5g and the other is 39.8g. When data is taken, the slope of the 1/a vs. (m1 + m2) graph turns out to be 6.77 1/N. What is the value of the frictional force of the pulley? (2 decimals and UNITS!) (g=9.8m/s2)

We have two masses hanging from a pulley of inertia mp and constant frictional force f. One mass is 55.9g and the other is 41.8g. When data is taken, the intercept of the 1/a vs. (m1 + m2) graph turns out to be 0.04s2/m and the frictional force of the pulley 0.31N. What is the value of the inertia of the pulley? (2 decimals and SI UNITS!) (g=9.8m/s2) (If you get a negative answer type it in even though it doesnt make sense physically)

2. Relevant equations

These are the equations I have:

for no friction:

1/a = (m1 + m2)/((m1 -m2)g)

for a system with friction:

(m1 - m2)g - f = (m1 + m2 + mp)a

1/a = [(m1 + m2)/((m1-m2)g - f)] + [mp/((m1-m2)g -f))]

3. The attempt at a solution

My solutions were totally outrageous I have no idea what i'm doing frankly i've studied this stuff for hours and can't wrap my head around it

**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!

# Homework Help: Help Plz pulley problems

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

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