What is the maximum radiation pressure exerted by sunlight in space (S = 1350 W/m²) on a highly polished silver surface? A)1.4 × 10−2 Pa B)0.12 Pa C)9.0 × 10−6 Pa D)4.5 × 10−5 Pa E)2.3 × 10−6 Pa

Question

Quizplus · Accepted Answer

The maximum radiation pressure exerted by sunlight in space is given by the formula:

P = S/c

where P is the radiation pressure, S is the solar constant (1350 W/m^2), and c is the speed of light (3 × 10^8 m/s).

Let A be the area of the silver surface. Then the radiation force on the surface is:

F = PA = (S/c)A

Let rho be the density of silver and let V be the volume of the silver. Then the weight of the silver is:

W = rho V g

where g is the acceleration due to gravity. For a small object in space, we can assume that g is negligible, so the weight is zero.

The maximum radiation pressure that the silver surface can withstand without being pushed away by the sunlight is equal to the radiation force divided by the area:

Pmax = F/A = (S/c)(1/rho)

For silver, rho = 10.5 g/cm^3 = 10500 kg/m^3. Substituting this value gives:

Pmax = (1350/3×108)/(10500) = 9.0 × 10^-6 Pa

Therefore, the best choice is C.

What Is the Maximum Radiation Pressure Exerted by Sunlight in Space