$1)$ A $1000$ W$/$m$^2$ beam of light is shone on a $1000$ m$2$ perfect blackbody light$-$sail of

a small spacecraft with total mass $100$ grams that is initially ata velocity of $0\mathrm{.}5$ c$.$ What

is the velocity of the spacecraft $1000$ seconds after the beam of light begins hitting the

sail?

$2)$ For the light sail in question $1,$ assume that in steady state the energy input from

the light beam is approximately equal to the energy emission from black body radiation.

What temperature would the light sail stabilize at$?$