How does hydroelectric energy work

What if a wave reaches a type of matter it cannot pass through? Does it just stop moving? If not, where does it go?

If you are trying to balance a seesaw and you have a higher mass on the left, should the mass on the right be placed at a greater distance or lower distance to balance it? Why?

What is the main organ in the respiratory System?

What is a major compound that makes up skin

The capacity to do work is called? A. temperature C. force

They are generally thought to be blank naturally occurring emotions that are present from birth

If an aircraft is loaded 90 pounds over maximum certificated gross weight and fuel (gasoline) is drained to bring the aircraft weight within limits, how much fuel should be drained?

3. Shortwave radio is broadcast between 3.50 and 29.7 MHz, To what range of wavelengths does this correspond? Why do you suppose this part of the spectrum is called shortwave radio?

How does a star's temperature change as the star ages from a main sequence star to a red giant and from a red giant to a white dwarf?

What factors in the atmosphere seem to have the greatest effect in the amount of radiation received from the sun?