Q. A planet of mass 8 × 10^24 kg is at location ‹ -4 × 10^11, 7 × 10^11, 0 › m. A star of mass 7 × 10^30 kg is at location ‹ 5 × 10^11, -5 × 10^11, 0 › m. What is the force exerted on the planet by star? (It will probably be helpful to draw the diagram, including the relevant vectors.)
Q. A 75{rm m}-long train begins uniform acceleration from rest. The front of the train has a speed of 23 {rm m/s} when it passes a railway worker who is standing 150 {rm m} from where the front of the train started. What is speed of last train compartment?