A planet of mass 8 × 1024 kg is at location ‹ −5 × 1011, 8 × 1011, 0 › m. A star of mass 9 × 1030 kg is at location ‹ 4 × 1011, −6 × 1011, 0 › m. What is the force exerted on the planet by the star? (It will probably be helpful to draw a diagram, including the relevant vectors.)

(a) Find the magnitude of the gravitational force (in N) between a planet with mass 8.00 ✕ 1024 kg and its moon, with mass 2.50 ✕ 1022 kg, if the average distance between their centers is 2.90 ✕ 108 m. (Answer in N)   (b) What is the moon's acceleration (in m/s2) toward the planet? (Enter the magnitude.) Answer in m/s2 (c) What is the planet's acceleration (in m/s2) toward the moon? (Enter the magnitude.) Answer in m/s2

(a) Find the magnitude of the gravitational force (in N) between a planet with mass 7.00 ✕ 1024 kg and its moon, with mass 2.20 ✕ 1022 kg, if the average distance between their centers is 2.50 ✕ 108 m. (b) What is the moon's acceleration (in m/s2) toward the planet? (Enter the magnitude.) (c) What is the planet's acceleration (in m/s2) toward the moon? (Enter the magnitude.)

One dimension. In the figure, two point particles are fixed on an x axis separated by distance d. Particle A has mass mA and particle B has mass 5.00 mA. A third particle C, of mass 88.0 mA, is to be placed on the x axis and near particles A and B. In terms of distance d, at what x coordinate should C be placed so that the net gravitational force on particle A from particles B and C is zero? y A B x