- #1

Lil_Aziz1

- 21

- 1

My question is, why does the book use force of gravity as the force acting on the pulley instead of the tension? the book did this problem previously using only Newton's second law, i.e.,

I did the angular momentum problem but replaced [tex]m_{1}g[/tex] and [tex]m_{2}g[/tex] with [tex]T_1=m_1(g-a)[/tex] and [tex]T_2=m_2(g+a)[/tex], respectively. Consequently, for linear acceleration I got [tex]a=\frac{m_1-m_2}{m_1+m_2+0.5M}\frac{g}{2}[/tex] (notice the g/2)

Can anyone explain to me why it's doing that?

Thanks in advance.