InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Two insulated copper sphere of charges +10 mu C and -20 mu Chave their centres seprated by a distance of 10 cm . What is the force of attraction if they placed. a in free space b. in water of dielectric constant 81. |
|
Answer» Solution :Data supplied ` r=10 xx 10 ^(-2) m.` ` q_1 =10 mu C =10 xx 10^(-6) C , q_2 = 20 MUC =20 xx 10 ^(-6 ) C ` a. ` "" F_("AIR") =(1)/( 4pi in _0) (q_1q_2)/( r^(2)) ` ` F_(air) =( 9xx 10^(9) xx10 xx 10 ^(-6)xx-20xx10 ^(-6))/( (10xx 10 ^(-2))^(2)) =-180 N` b. ` F_("water")=(1)/( 4piin _0) =(q_1q_2)/( r^(2)) =(air )/(in_r) =(-180)/(81)=-2.22N` NEGATIVE sign indicates that the force is attractive. |
|