What happens when a ray of light moves from air to water?
its speed changes.
its color changes.
its direction changes.
it's absorbed by water.

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?