Black holes

What happens when a star's core is less than 1.4 times the mass of the Sun?

• It forms a black hole

• It becomes a neutron star

• It explodes

• It becomes a white dwarf

What is the size of a white dwarf?

• Size of the Moon

• Size of the Sun

• Size of the Earth

• Size of Jupiter

What happens if the core of a star is between 1.4 and 2.8 times the Sun's mass?

• It becomes a white dwarf

• It forms a black hole

• It collapses further into a neutron star

• It explodes

What force can stop the collapse of a star's core if its mass is more than 2.8 times the Sun's?

• Electromagnetic force

• Gravitational force

• Nuclear force

• Weak force

What is the escape velocity of the Earth?

• 11 km/sec

• 600 km/sec

• 150,000 km/sec

• Half the speed of light

What is the escape velocity of a neutron star?

• Half the speed of light

• 600 km/sec

• 150,000 km/sec

• 11 km/sec

What happens when the escape velocity at the surface of a black hole is equal to the speed of light?

• It shrinks further

• It explodes

• It becomes a white hole

• Nothing can escape

What is the name given to the surface around a black hole where the escape velocity is the speed of light?

• Event Horizon

• White Dwarf

• Neutron Star

• Singularity

What is the minimum mass required for a stellar-mass black hole to form?

• 3 times the Sun's mass

• 1 times the Sun's mass

• 4 times the Sun's mass

• 2 times the Sun's mass

What happens to time near a black hole?

• It reverses

• It speeds up

• It slows down

• It stops