Answer:
[tex]3.56\mu C/m^2[/tex]
Explanation:
The potential at the surface of the spheres is same as they are connected with a conducting wire.
Calculate electric field strength at the surface of smaller sphere.
[tex]R_s=5.60 cm\\R_L=10.5 cm\\E_L=215 kV/m\\ \frac{E_s}{E_L}=\frac{R_L}{R_s}\\E_s= \frac{10.5}{5.60}\times 215\times 10^3 =4.03\times10^5V/m[/tex]
[tex]\sigma_s=\epsilon_oE_s\\\sigma_s=8.85\times10^{-12}\times 4.03\times10^5\\\sigma_s=35.66\times 10^{-7}C/m^2[/tex]