It takes 3.3 j of work to stretch a hooke's-law spring 15 cm from its unstressed length. how much the extra work is required to stretch it an additional 11.3 cm? answer in units of j.

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.

This is the substance(s) formed in a chemical reaction.

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects