Ascreen is placed 50cm from a single slit illuminated with 690nm light. if the distance between the first and third dark fringes in the diffraction pattern is 3mm.
a) find the width of the slit
used w=(2\lambdal)/d to get 500 mm
b) find the width of the central bright fringe using w=(2\lambdal)/d .

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.