A community seeks to develop a maglev train operation. Which of the following is most likely their technical motivation for choosing this option?(1 point) They need trains that can cover particularly long distances.

They hope to employ lighter weight materials that reduce costs.

They do not want to rely on any supply of electricity.

They seek a rail line not affected by friction.

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.

Why is it important always to use horizontal bars in unit fractions when performing unit conversions?

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.