posted by J on .
During 2004, japanese scientists successfully tested two solar sails. One had somewhat complicated shape that we shall model as a disk 9 m in diameter and 7.5 um thick. The intensity of solar energy at this location was about 1400 W/m
^2. (a) What force did the sun's light exert on this sail, assuming that it struck perpendicular to the sail and that the sail was perfectly reflecting? (b) If the sail was made of magnesium, of density 1.74 g/cm^3, what acceleration would the sun's radiation give to the sail? (c) Does the acceleration seem large enough to be feasible for space flight? In what ways could the sail be modified to increase its acceleration?
If perfectly reflecting the radiation pressure is 2 I/c
p = 2 *1400 W/m /3*10^8 m/s
= 9.4 *10^-6 Pascals
That is like 10^-10 atmospheres, like tiny
multiply the p by pi (D/2)^2 to get force
calculate mass from density and do a = F/m