Question

A laser beam of pulse power ${10}^{12}W$ is focussed on an object of area ${10}^{-4}{cm}^2$. The energy flux in $W/{cm}^2$ at the point of focus is

• A. ${10}^4$
• B. ${10}^8$
• C. ${10}^{16}$
• D. ${10}^{20}$

Answer 1

The correct option is C ${10}^{16}$

We knows electric flux $\left(\varphi \right)=\frac{Pulsepower}{Area}=\frac{{10}^{12}}{{10}^{-4}}={10}^{16}W/{cm}^2$