Physics (AS & A Level) · May / June 2019 · Paper 11 · Question 2

The luminosity L of a star is given by L = 4πr²σT⁴ where r is the radius of the star, T is the temperature of the star and σ is a constant with units W m⁻² K⁻⁴. What are the SI base units of L?

1. Akg m² s⁻¹
2. Bkg m² s⁻²
3. Ckg m² s⁻³
4. Dkg m² s⁻⁴

As printed in the paper