ملتقى الفيزيائيين العرب - طلب مساعدة في حل assignment

السلام عليكم ورحمة الله وبركاته

عندي assignment باقي منه فقرتين من سؤالين ارجو المساعدة في الحل في اقرب وقت

:Q1

consider a planet with a circular orbit about the sun of radius R and period T. let the sun have mass M and we suppose the mass of the planet is negligible compared to M

a) the mass of the sun is approximately 2 * 10^30 kg. the radius of Earth's planet is approximately 1.5 * 10^11 m. find the approximation for gravitational constant G. Express your answer in the appropriate
units

:Q2

A comet of mass m, negligible compared to the mass M of the sun, .is observed to have a parabolic orbit

a) suppose the comet collides with Earth. what is its speed when it reaches Earth? Express your answer in terms of the radius R of Earth's orbit, the mass M of the sun, and the gravitational constant G
neglect the gravitational effect of the Earth on the comet

مع العلم ان:
R: the adius of Earth's orbit is approximately 1.5 * 10^11 m
M: the mass of the sun is approximately 2 * 10^30 kg