Question
The Sun consists mostly of two elements.
What are these two elements?
A helium and nitrogen
B hydrogen and helium
C hydrogen and oxygen
D oxygen and nitrogen
▶️Answer/Explanation
Ans: B
Question
Light from distant stars is redshifted.
What is redshift?
A a decrease in observed wavelength caused by a star moving away from the Earth
B a decrease in observed wavelength caused by a star moving towards the Earth
C an increase in observed wavelength caused by a star moving away from the Earth
D an increase in observed wavelength caused by a star moving towards the Earth
▶️Answer/Explanation
Ans: C
Question
The graph shows the energy radiated by the Sun at different wavelengths. Most of the energy is radiated in just three parts of the electromagnetic spectrum, labelled \(P, Q\) and \(R\).
Which parts of the electromagnetic spectrum are \(\mathrm{P}\) and \(\mathrm{R}\) ?
▶️Answer/Explanation
Ans:D