In astronomy order of magnitude estimation plays an important role. The derivative (dp)/(dt) can be taken difference ration (DeltaP)/(Deltar). Consider the star has a radius R, pressure at its centre is P_(e) and pressure at outer layer is zero is the average mass is (M_(Q))/2 and average radius (R_(o))/2 then the expression for P_(c) is

In astronomy order of magnitude estimation plays an important role. Th

1.	In astronomy order of magnitude estimation plays an important role. The derivative (dp)/(dt) can be taken difference ration (DeltaP)/(Deltar). Consider the star has a radius R, pressure at its centre is P_(e) and pressure at outer layer is zero is the average mass is (M_(Q))/2 and average radius (R_(o))/2 then the expression for P_(c) is
Answer» `P_(c)=3/2(GM_(0)^(2))/(piR_(0)^(4))` `P_(c)=2/(3pi)(GM_(0)^(2))/(R_(0)^(4))` `P_(c)=2/3(GM_(0)^(2))/(piR_(0)^(4))` `P_(c)=3/2(GM_(0)^(2))/(R_(0)^(4))` Solution :The net force acting on the system is `\|vec(F)_(1)+vec(F)_(2)\|=0` `RARR ` the linear MOMENTUM of the system is conserved `rArr m_(A)v_(A)=m_(B)v_(B)` `rArr v_(A)=(m_(B))/(m_(A))v_(B)=2/1xx3.6=7.2cm//hr` `=(7.2xx10^(-2))/(3.6xx10^(3))=(7.2xx10^(-2))/3600=(7.2xx10^(-2))/(3.6xx10^(3))=2xx10^(-5)` In `10^(-5)m//s, v_(A)=2`