science-revision cards-class 7 final exam Flashcards
what are telescopes
Device to see far away objects
what is radiant energy
energy from electromagnetic waves
cool stars emits_____wavelegth
longer
hot stars emits_____wavelength
shorter
who is an astronomer
scientists whom study about space
what are the 2 types of Earth base telescope
optical telescope – Radio telescope
what are 2 types of optical telescopes
refracting telescope – reflecting telescope
why are optical telescopes kept at high mountains
the light will be distracted by water - vapor and gases
what lens does a refracting telescope use
convex lens
what lens does a reflecting telescopes use
curved mirror
were can electromagnetic waves can travel through
space - matter
how many minutes does sunlight takes to reach Earth
8 minutes to reach Earth
longest wavelength
Radio waves
shortest wavelength
Gamma Waves
highest wavelength
Gamma Waves
