Phys__ho|t_ch7_Circu|ar Motion 8t Gravitationpdf Sample Problem c Find the distance between a 0.300 kg billiard ball and a 0.400 kg billiard ball if the magnitude of the gravitational force between them is 8.92 x 10'" N. o ANALYZE Given: m1 = 0.300 kg Wt2 = 0.400 kg Pg = 8.92 x 10-\" N Unknown: r: ? e SOLVE Use the equation for Newton's law of universal gravitation, and solve for r. m m F = G 1 2 g ,2 . m m r: G 11: 2 8 Nom2 X (0.300 kg)(0.400 kg) kgz 8.92 x 10'11N (6.673 x 10'll r: 3.00 x 10'1 m 1 . What must be the distance between two 0.800 kg balls if the magnitude of the gravitational force between them is equal to that in Sample Problem C? 2. Mars has a mass of about 6.4 x 1023 kg. and its moon Phobos has a mass of about 9.6 x 1015 kg. If the magnitude of the gravitational force between the two bodies is 4.6 x 1015 N, how far apart are Mars and Phobos? . 3. Find the magnitude of the gravitational force a 66.5 kg person would experience while standing on the surface of each of the following bodies: Celestial Body Mass Radius a.Earth 5.97 x 1024 kg 6.38 x 105m b. Mars 6.42 x lonkg 3.40 x 105m c. Pluto 1.25 x 1022 kg 1.20 x 106mm