Title: Interactive Video

Multiple Choice Question

Death of a star

Q: How a star dies depends on its ...
- colour
- speed
- mass (correct)
- distance from the Earth
Feedback (0 to 99%): The death of a star is determined by the mass of the star
Feedback (100 to 100%): Awesome!

Multiple Choice Question

Lifetime of stars

Q: Star A has a larger mass than star B.  Which of the following is true?
- A has a shorter livetime than B. (correct)
- A has a longer lifetime than B.
- A and B have equal lifetimes.
- None of these are true.
Feedback (0 to 99%): Careful, it might seem like a high mass star should live longer but remember that the higher mass means it burns its material faster.
Feedback (100 to 100%): Excellent!

True False Question

Core fusion

Q: Many different chemical elemetns can be created in the core of a star during its lifetime.
A: true
If right: Correct!
If wrong: Careful, stars start fusing hydrogen into helium but later in life they are able to fuse more elements.

Multiple Choice Question

When iron dominates the core

Q: When the chemical element iron dominates the core of a star, the star ...

Choose all that apply
- no longer generates the force needed to counteract gravity. (correct)
- has a central core that collapses and produces a powerful explosion called a supernova. (correct)
- shuts down and no longer produces any light.
Feedback (0 to 65%): Good effort. The supernova occurs because of core collapse.
Feedback (66 to 100%): Excellent!

True False Question

What size star forms a black hole

Q: Only massive stars form black holes.
A: true
If right: Correct!
If wrong: Careful, only truly massive stars will ever become a black hole.

True False Question

Do we understand black holes?

Q: Scientists have an excellent understanding of what is inside a black hole.
A: false
If right: You are correct! We still have a lot to learn about black holes.
If wrong: Unfortunately we don't.

Multiple Choice Question

Detecting stellar black holes

Q: Astronomers have detected black holes by ...

Select all that apply.
- Observing the effect of their gravity on stars orbiting them. (correct)
- Observing them directly through telescopes.
- Observing matter that orbits just outside the black hole. (correct)
Feedback (0 to 65%): Good try! We have actually only ever observed one black hole directly and that took a telescope the size of the Earth to do it!
Feedback (66 to 100%): Awesome!

Multiple Choice Question

Event Horizon

Q: When light becomes trapped inside a black hole forever, the light has crossed over the black hole's ...
- event horizon (correct)
- singularity
- jets
- magnetic field lines
Feedback (0 to 99%): Good effort! The event horizon is the point of no return for a black hole.
Feedback (100 to 100%): Excellent!

Multiple Choice Question

Jets

Q: The spin of a black hole is responsible for which observed feature of a black hole?
- The trapping of light inside the black hole.
- Jets on either side of the black hole (correct)
- Gravitational forces.
- Mass,
Feedback (0 to 99%): Good effort! Spinning black holes produce jets.
Feedback (100 to 100%): You Rock!

Multiple Choice Question

Supermassive black holes

Q: Astronomers have found most supermassive black holes located ...
- near the outer edge of our solar system.
- in the centre of our galaxy.
- on the edge of galaxies.
- in the centres of spiral galaxies. (correct)
Feedback (0 to 99%): Good try! Supermassive black holes are found at the centre of most galaxies.
Feedback (100 to 100%): You're awesome!

Choose the correct statement.

Feedback (0 to 100%): Awesome job!

Credits: Black Holes; by Perimeter Institute of Theoretical Physics; 2018; licence GNU GPL v3