Why would heating the gas in an air balloon make the balloon rise?

Which of these rocks are formed by volcanic activity? select the two correct answers. a. limestone b. granite c. marble d. basalt e. sandstone

A student had a sample of pure water, and added an unknown substance to it. the student noticed that the hydroxide ion concentration in the solution increased as the substance was added. what is true about this newly formed solution?

Describe why sleeping on the top bunk, in a bunk bed, would be a great choice in the winter but a bad choice for the summer.

Without the force of friction, people would not be able to walk.

A sinusoidal transverse wave travels along a long, stretched, string. the amplitude of this wave is 0.0885 m, it's frequency is 4.31 hz, and its wavelength is 1.21m.

Sound travels slow in cold air. Why does the speed of sound depend on air temperature?

A tow truck pulls a 500 kg car so that the car accelerates 2 m/s2. What is the net force on the car? 250 N 498 N 1000 N 502 N

Which force keeps you near earths surface?

Name one process that requires a force in the human body.

Which describes the electric forces inside an atom