Question

A laser (electromagnetic wave) has the maximum electric field strength of 1.0x1011 V/m. What is the force the laser applies on a mirror (totally reflective) of 5.0 mm2 area? A. 2.76 x105N B. 1.21 x106N C. 1.94 x106N D.4.43 x105 N E. 7.82 x104N

Answer 1

The correct option is D

Step-by-step explanation:

From the question we are told that

The maximum electric field strength is
`E = 1.0 *10^(11) \ V/m`

The area is
`A = 5.0 \ mm^2 = 5.0 *10^(-6) \ m^2`

Generally the force the laser applies is mathematically represented as

`F = \epsilon_o * E ^2 * A`

Here
`\epsilon_o = 8.85*10^(-12) C/(V \cdot m)`

`F = 8.85*10^(-12) * (1.0 *10^(11)) ^2 * 5.00*10^(-6 )`

=>
`F = 4.43 *10^(5) \ N`