Warmup: Finish #4 and #5 Planet Orbital Period Orbital Radius (AU) Mercury Venus Earth 11 Moon Mars Jupiter Saturn Uranus Neptune Pluto )Try to determine the formula for the ratio of the average orbital radius to the orbital period. Use a scatterplot to help you do this. 2)Should Kepler’s Law apply in the same way to the Moon? Does it? Why or why not? 3)If the amount of sunlight striking an object obeys an inverse-square law, how much less sunlight per square meter does Pluto get than Earth? How much more sunlight per square meter does Mercury get? 4)If it takes light travelling at a velocity of 3 x 10 8 m/s 8 minutes to get to Earth, how many meters is 1 AU? 5)If the mass of the Sun is 2 × kg, and the mass of Earth is 6 x kg, what is the force exerted by the sun?

Practice Quiz Answers 1)A 2)C 3)A,b,c 4)More 5)More 6)Less 7)C 8)False; very tiny number, weak force 9)False; difficult but possible to measure 10)False; law calculatse how much they attract, theory attempts to explain why 11)E; they perceive no weight due to no normal force 14) False 15) False 16) False 17) False 18) False 19) False 20) False

M1M2rF E E E E E E E G 6.67E-11 M1rg 5.98E E E E E