Angular diameter of sun =
θ=1920′′
1920′′=(192060)1=321
=(3260)∘
1920=0.533∘
now, 180∘≡π rad
∴0.533∘≡(?)
∴θ=0.533×π180≈9.3×10−3 rad
let diameter of sun be d given that l=1.496×1011m
Now , θ=arcradius=dr
∴d=θl
∴d=9.3×10−3×1.496×1011
∴d=13.91×108
∴d=1.39×109m
diameter of sum is 1.39×109