BOOTCAMP EQUIVALENT EXPERIENCE SC.8.E.5.5

What does the HR diagram primarily show the relationship between?

• Temperature and distance

• Luminosity and temperature

Answer explanation

The HR diagram primarily shows the relationship between luminosity and temperature of stars, plotting them on a graph to illustrate how these two properties correlate, with hotter stars generally being more luminous.

On the HR diagram, where are the hottest stars located?

• Top right

• Top left

Answer explanation

On the HR diagram, the hottest stars are located in the top left. These stars are typically blue and have high temperatures, while cooler stars are found in the bottom right.

Which type of star is found in the upper right corner of the HR diagram?

• Red giants

• Blue supergiants

Answer explanation

Red giants are located in the upper right corner of the HR diagram, characterized by their large size and cool temperatures. In contrast, blue supergiants are found in the upper left, making red giants the correct choice.

What characteristic of stars is plotted on the vertical axis of the HR diagram?

• Temperature

• Luminosity

Answer explanation

In the HR diagram, the vertical axis represents luminosity, which indicates the total energy output of a star. Temperature is plotted on the horizontal axis, making luminosity the correct choice for the vertical axis.

Which of the following stars would be found on the main sequence of the HR diagram?

• A blue star

• A neutron star

Answer explanation

A blue star is a main sequence star, characterized by its high temperature and luminosity. Neutron stars, however, are remnants of supernovae and do not fall on the main sequence of the HR diagram.

What is the main sequence on the HR diagram?

• A diagonal band where stars spend most of their life

• A horizontal line of stars with the same temperature

Answer explanation

The main sequence on the HR diagram is a diagonal band where stars spend most of their life, fusing hydrogen into helium. This distinguishes it from other regions, such as the horizontal branch, which represents different stellar phases.

Which of the following best describes the stars located in the lower left of the HR diagram?

• Hot and dim

• Cool and bright

Answer explanation

The stars in the lower left of the HR diagram are classified as hot and dim. They have high temperatures but low luminosity, which is characteristic of certain types of stars, such as white dwarfs.

What does the position of a star on the HR diagram indicate about its life cycle?

• Its current stage in the stellar evolution

• Its chemical composition

Answer explanation

The position of a star on the HR diagram indicates its current stage in stellar evolution, reflecting its temperature and luminosity, which are key factors in understanding its life cycle.

Which of the following is true about white dwarfs on the HR diagram?

• They are very luminous

• They are very hot but not very luminous

Answer explanation

White dwarfs are located in the lower left of the HR diagram, indicating they are very hot but have low luminosity compared to other stars. This makes the statement 'They are very hot but not very luminous' the correct choice.

In the HR diagram, what does a star's position along the main sequence primarily depend on?

• Its age

• Its mass

Answer explanation

A star's position along the main sequence in the HR diagram primarily depends on its mass. More massive stars are hotter and brighter, placing them higher on the main sequence, while less massive stars are cooler and dimmer.