Monday

July 28, 2014

July 28, 2014

Posted by **Chris** on Sunday, June 10, 2012 at 5:44pm.

The center of the disk is (0,0)

The center of the hole is at (2,0)

- Physics! -
**Elena**, Sunday, June 10, 2012 at 6:18pmx1=0, y1=0, x2=2m, y2=0.

R=4 m, r=1 m.

y(c.m.) =0

x(c.m.) = (A1•x1 –A2•x2)/(A1-A2)=

=(A1•0-A2•x2)/(A1-A2)

= - πr²•2/π(R²-r²) =

= - 1•2/(16-1) =2/15 = - 0.133 m

Center of mass x=- 0.133 m, y = 0

- Physics! -
**Count Iblis**, Sunday, June 10, 2012 at 6:20pmHint: If you take the equation for the cente of the mass, and you multiply that by the total mass, you get:

Integral of rho(r) r d^3r

This satisfies the superposition principle, the result for a density function rho1 + rho2 is the same as that for rho1 and rho2 seperately and then added together.

This means that you can add up the what you get for a disk without a hole to what you get for a hypothetical disk of negative mass. You then divide the result by the total mass.

**Related Questions**

physics - A curcial part of a piece of machinery starts as a flat uniform ...

Physic - A machine part is made from a uniform solid disk of radius R = 0.161 m ...

Physics - A machine part is made from a uniform solid disk of radius R and mass ...

physics - A spherical shell of uniform charge density σ has a circular hole...

physics - A spherical shell of uniform charge density σ has a circular hole...

Physics - A thin rectangular plate of uniform area density σ1 = 1.01 kg/m2 ...

physics - A thin rectangular plate of uniform area density σ1 = 1.00 kg/m2 ...

Physics - A flat uniform circular disk (radius = 2.10 m, mass = 1.00 102 kg) is ...

physics helpppp - Figure 10-35a shows a disk that can rotate about an axis at a ...

Physics - A solid cylindrical disk has a radius of 0.18 m. It is mounted to an ...