Part A Estimate the radiation pressure due to a bulb that emits 25 W of EM radia
ID: 1490421 • Letter: P
Question
Part A
Estimate the radiation pressure due to a bulb that emits 25 W of EM radiation at a distance of 8.0 cm from the center of the bulb. Assume that light is completely absorbed.
Express your answer to two significant figures and include the appropriate units.
P =
Part B
Estimate the force exerted on a fingertip at this point. Suppose that the area of the fingertip is 1.4 cm^2 . Assume that light is completely absorbed.
Express your answer to two significant figures and include the appropriate units.
F =
Explanation / Answer
A) Pressure, p = S/c = (P/4pi*d2)/c = [25/( 4* 3.14* 0.08^2)]/ 3* 10^8 = = 314.94 N/m2 (ans)
B) F = pressure * Area = 314.94*1.4*10-4 = 4.40*10-2 N (ans)