Hypothesize how the astronauts Neil Armstrong and Buzz Aldrin could talk to each other on the moon if the moon does not have an atmosphere for the sound waves to travel through?

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

If a simple machine reduces the strength of a force, what must be increased?

Abowling ball rolling down the lane toward the pins has gravitational potential energy. a. no b. a lot of c. a little