InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
A planet of radius `R=(1)/(10)xx(radius of Earth)` has the same mass density as Earth. Scientists dig a well of depth`(R )/(5)` on it and lower a wire of the same length and a linear mass density `10^(-3) kg m(_1)` into it. If the wire is not touching anywhere, the force applied at the top of the wire by a person holding it inplace is (take the radius of Earth`=6xx10^6m` and the acceleration due to gravity on Earth is `10ms^(-2)`A. 96 NB. 108 NC. 120 ND. 150 N |
|
Answer» Correct Answer - B `E_(G)=(4piGrrho)/(3)` `dF=E_(G)lamdadr` `F=underset((4R)/(5))overset(R)int(4piGrholamda)/(3)rdr=(4piGrholamda)/(3)[(r^(2))/(2)]_((4R)/(5))^(R)` `=(4piGrholamda)/(3xx2)[R^(2)-(16R^(2))/(25)]=(4pi)/(6)Grholamdaxx(9)/(25)R^(2)` `F=(4pi)/(6)Gxx(M)/((4pi)/(3)R_(e)^(3))xxlamdaxx(9)/(25)xx(R_(e)^(2))/(100)` After solving [`Fimplies108N]` |
|