Unit 8 - Astrophysics revision

A large collection of billions of galaxies...

A large collection of billions of stars...

A collection of planets orbiting a common star...

Our star is part of the ... galaxy

What are the units for gravitational field strength?

• kg/N

• N/Kg

• Kg

• N

The orbits of comets are...

• Slightly eliptical

• Eliptical

• Highly eliptical

• Circular

Where do comets have a greater speed?

• Nearer the star

• Further from the star

• At a mid distance

What is the correct equation for orbital speed?

• $v\ =\ 2\pi Tr$

• $v=\frac{\pi r}{2T}$

• $v=\frac{2\pi r}{T}$

• $v=\frac{2\pi}{rt}$

Stars begin life in a cloud of dust and gas called a...

The dust in the nebula clumps together, hydrogen begins to fuse and causes great outward pressure. This outward pressure balances with the inward pressure of gravity and a ... is born.