Earth's atmosphere is able to gradually refract light rays:
A) only when it is very dry.
B) only when the sun is very high in the sky.
C) because of the changing density of air as you get closer to the surface.
D) because of air pollution that is present.
Question 2
Which of the following is not cited as a factor in helping to reduce air pollution?
A) use of more alternative, clean energy sources such as wind and solar
B) increased vehicle fuel-efficiency
C) uses of alternative and public transportation
D) stricter air emission regulations
E) increased use of coal as an energy source
The Sun is the nearest star to Earth.
The tenuous atmosphere of Mars, visible on the horizon in this low-orbit photo
Pairs of heavy and light chains combine to form a Y-shaped molecule
Gravitational Redshift The color of light from the same object located at diffe
Light Waves in the Electromagnetic Spectrum
Using a bright light makes seeing where the smoke is coming from easier. In this case, smoke was ...