The Total solution for NCERT class 6-12
Check that the ratio ke2/Gmemp is dimensionless. Look up aTable of Physical Constants and determine the value of this ratio. What doesthe ratio signify?
The given ratio is
Where,
G = Gravitational constant
Its unit is N m2 kg−2.
me and mp =Masses of electron and proton.
Their unit is kg.
e =Electric charge.
Its unit is C.
∈0 = Permittivity of free space
Its unit is N m2 C−2.
Hence, the given ratio isdimensionless.
e = 1.6 ×10−19 C
G = 6.67 × 10−11 Nm2 kg-2
me= 9.1 × 10−31 kg
mp =1.66 × 10−27 kg
Hence, the numerical value of thegiven ratio is
This is the ratio of electricforce to the gravitational force between a proton and an electron, keepingdistance between them constant.