suppose that all 7.5 billion people on earth were in the same place. If the kinetic energy required for one person to jump 0.5 meters is 294 J, what is the magnitude of acceleration the earth feels if every person jumps with an accelerations of 14.8 m/s^2

When an object is heated it contracts. a. true b. false

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 !

What are the similarities & differences between a thermistor and a light dependent resistor in physics?