What is a light year defined as?
The distance travelled by a satellite in one year
The time it takes light to travel from one solar system to another
The distance travelled by light in one year
Put these members of the EM spectrum into correct order from high frequency to low frequency: infrared, ultraviolet, X-rays, radio waves, visible light
X-rays, ultraviolet, visible light, infrared and radio waves
Radio waves, infrared, visible light, ultraviolet and X-rays
X-rays, infrared, visible light, ultraviolet and radiowaves
Which of the following is a detector for radiowaves?
Aerials
Blackened thermometers
Photographic film
Which of the following is a detector for gamma rays?
GM tubes
What is a possible source for infrared waves?
Cool objects
Warm objects
Radioactive decay
What is a possible source for visible light?
The Sun
What is a possible use for Infrared waves?
Remote controls
Communication
Medical tracers
What is a possible use for ultraviolet waves?
Photography
Making vitamin D
The diameter of the Milky Way galaxy is approximately \(9\cdot8 \times 10^{20}\, m\). What is the equivalent distance expressed in light years?
\(1\cdot04 \times 10^{5}\,\) light years
\(3\cdot10 \times 10^{13}\,\) light years
\(9\cdot27 \times 10^{36}\,\) light years
A section of spectral lines from a distant nebula are shown.
Sections of the spectral lines of four elements are also shown
Which element(s) are present in the nebula?
None of them
Helium and mercury
Hydrogen and nitrogen