In studying effects of collisions between galaxies, astronomers usually make use of space telescopes.
Astronomy deals with the study of outer space. The study focuses on planets and other celestial bodies. Generally telescopes are used to study outer space. The particular type of telescope that is used depends on the need.
In studying effects of collisions between galaxies, astronomers usually make use of space telescopes.
When the ambulance is coming towardss you the waves are smushed together and sound higher pitched but then it passes you and when tracveling away the waves are scretched out so the whee whoo sounds lower and that is because of the doppler effect
frequency it the measure of the wave length. The measure of the peaks and troughs is how you measure the frequency. the distance between these is the wave length.