# Need help at this very minute with physics

posted by
**John** on
.

In Figure 10-53, two blocks, of mass m1 =400 g and m2 =600 g, are connected by a massless cord that is wrapped around a uniform disk of mass M = 500 g and radius R = 12.0 cm. The disk can rotate without friction about a fixed horizontal axis through its center; the cord cannot slip on the disk. The system is released from rest.

(a) Find the magnitude of the acceleration of the blocks.

m/s2

(b) Find the tension T1 in the cord at the left.

N

(c) Find the tension T2 in the cord at the right.

N

First, calculate the moment of inertia for the pulley.

Then, notice on the pulley that angular acceleration is related to cord acceleration by

alpha*radius= linear acceleration.

Now, writing a system equation...

m2*(g-a)= pulling force by gravity

I*alpha= Torque on pulley

I*alpha/radius = force on pulley extreme

I*acceleration/radius^2

m1*a= tension on m1

or

m2*(g-a)=I*a /r^2+m1*a

solve for a.

check my thinking.

i need help with writing system of equations for ages