Q. Three astronauts, propelled by jet backpacks, push and guide a 114 kg asteroid toward a processing dock, exerting the forces, with F1 = 32 N, F2 = 52 N, F3 = 39 N, θ1 = 30°, and θ3 = 60°. What is the (a) magnitude and (b) angle (measured relative to the positive direction of the x axis) of the asteroid's acceleration?
Q. A lunar lander is making its descent to Moon Base I. The lander descends slowly under the retro-thrust of its descent engine. The engine is cut off when the lander is 5.0 m above the surface and has a downward speed of 0.8 m/s. With the engine off, the lander is in free fall.
What is the speed of the lander just before it touches the surface?
The acceleration due to gravity on the moon is 1.6 m/s^2.