Question

What should be the ratio of the energies of radiations whose wavelengths are $3000\mathring{A}$ and $6000\mathring{A}$ ?

• A. $1:2$
• B. $2:1$
• C. $1:3$
• D. $3:4$

Answer 1

The correct option is A $1:2$

Area of a sector $=\frac{radian}{2\pi }\times \left(\pi r^2\right)$

$\frac{\frac{11}{6}\pi }{2\pi }\times \pi r^2=33\pi$

$\pi r^2$ area of circle (A)

$\frac{11}{12}\times A=33\pi$

$A=\frac{33\times 12}{11}\pi$

$A=36\pi$ unit square is area of circle