The acceleration due to gravity at the surface of a planet depends on the planet's mass and size; therefore other planets will have accelerations due to gravity different from 9.8 m/s2. imagine an astronaut stands on an alien planet, which has no atmosphere, and throws a rock with a speed of 7.45 m/s in the horizontal direction, releasing it at a height of 1.40 m above the surface of the planet. the rock hits the surface a horizontal distance of 8.90 m from the astronaut. find the magnitude of the acceleration due to gravity on this alien planet.

Explain earth's motion, using the terms "precession" and "rotation" in your answer.

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

Positrons are spontaneously emitted from the nuclei of