A Level Physics: Astronomy Quiz

What is luminosity defined as?

• The surface temperature of a star

• The observed intensity of radiation on Earth

• The total power output of radiation emitted by a star

• The distance between a star and the Earth

What unit is luminosity measured in?

• Meters (m)

• Watts (W)

• Kelvin (K)

• Joules (J)

What does radiant flux intensity measure?

• The surface area of a star

• The distance of a star from Earth

• The total power output of a star

• The observed amount of intensity of radiation on Earth

According to the inverse square law, how does light intensity change with distance?

• It increases linearly with distance

• It decreases exponentially with distance

• It decreases with the square of the distance

• It remains constant regardless of distance

What is a standard candle in astronomy?

• A type of star with a known luminosity

• A method for measuring distances in space

• A tool for observing stars

• A type of telescope

Which of the following is an example of a standard candle?

• Neutron stars

• Black holes

• Red giant stars

• Cepheid variable stars

What does Wien's Displacement Law relate?

• Radiant flux to luminosity

• Wavelength to surface temperature

• Intensity to distance

• Luminosity to distance

What is the equation for Wien's Displacement Law?

• λT = 2.9 × 10^3 m K

• λT = 2.9 × 10^-3 m K

• λT = 2.9 × 10^-2 m K

• λT = 2.9 × 10^2 m K

What does the Stefan-Boltzmann Law state?

• Luminosity is proportional to the fourth power of temperature

• Luminosity is proportional to the square of the radius

• Luminosity depends only on distance

• Luminosity is constant for all stars

What is the formula for calculating luminosity using the Stefan-Boltzmann Law?

• L = 4πr^2σT^4

• L = 4πσT^4

• L^2 = 4πr^2T^4

• L = rσT^4