which statement is true about equilibrium density for a density wave in a spring coil? Choose the correct answer.

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 18oc and exits at 6.0 bar. the refrigerant undergoes a throttling process. determine the temperature, in oc, and the quality of the refrigerant at the exit of the expansion valve.

What are similarities and differences between refraction, reflection, diffraction and absorption?

The air that we breath is made mostly of which gaseous molecule