The expression of the electric flux is
Here,
Q = Total charge enclosed in the closed surface
= Permittivity due to free space
Rearranging to find the charge,
Replacing with our values we have finally
The charge enclosed by the box is 0.1684nC
The sign of the charge can be decided by using the direction of the flux. The charge enclosed by the cube can be calculated by using the electric flux and the permitivity of free space.
Answer:
speed of star is 1.37 × m/s
it is approaching to earth because wavelength of star is decreasing than rest
if emit same wavelength it does not move anywhere
it will remain steady condition with respect earth
Explanation:
given data
wavelength = 656.5 nm
rest wavelength = 656.8 nm
to find out
the speed of the star , is it approaching
solution
we know here equation that is
wavelength shift / wavelength at rest = velocity of source / speed of light
so put all value and find
velocity of source = 3 × × 3 ×
/ 656.8 ×
velocity of source star = 1.37 × m/s
and
it is approaching to earth because wavelength of star is decreasing than rest
and
if emit same wavelength it does not move anywhere
it will remain steady condition with respect earth