A) \[2.4\times {{10}^{-6}}\]
B) \[1.2\times {{10}^{-7}}\]
C) \[3.6\times {{10}^{-8}}\]
D) \[5.6\times {{10}^{-5}}\]
Correct Answer: B
Solution :
Pressure of lighten totally reflecting surface \[P=\frac{2I}{C}\](C-velocity of light) \[P=\frac{F}{A}=\frac{2I}{C}\] \[\Rightarrow \] \[F=\frac{2IA}{C}=\frac{2\times 12\times 1.5\times {{10}^{-4}}}{{{10}^{-4}}\times 3\times {{10}^{8}}}\] \[=\frac{8\times 15\times {{10}^{-8}}}{10}=12\times {{10}^{-8}}=1.2\times {{10}^{-7}}N\]You need to login to perform this action.
You will be redirected in
3 sec