Astrophysics

Worked examples (9)

• 1Match the unit to the quantity (Getting started)
• 2Weight on another world (Getting started)
• 3Find the field strength (Getting started)
• 4Convert an orbital period (Building confidence)
• 5Working in standard form (Building confidence)
• 6Mass and weight compared (Building confidence)
• 7Is the answer sensible? (Stretch)
• 8N/kg and m/s² (Stretch)
• 9A full conversion and calculation (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
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Worked examples (9)

• 1State the structure (Getting started)
• 2Order by size (Getting started)
• 3Star or planet? (Getting started)
• 4What is in the solar system (Building confidence)
• 5What is a galaxy? (Building confidence)
• 6Natural and artificial satellites (Building confidence)
• 7Why the Sun looks special (Stretch)
• 8Looking into the past (Stretch)
• 9The full chain (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1Why g differs on the Moon (Getting started)
• 2Weight on another planet (Getting started)
• 3Find g from a weight (Getting started)
• 4What keeps a moon in orbit (Building confidence)
• 5Is an orbiting object accelerating? (Building confidence)
• 6What if gravity disappeared? (Building confidence)
• 7Why satellites do not fall down (Stretch)
• 8Why astronauts float (Stretch)
• 9The four orbiting cases (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1Compare the three orbits (Getting started)
• 2Why a comet's speed changes (Getting started)
• 3What does a moon orbit? (Getting started)
• 4The energy view (Building confidence)
• 5Why a planet's speed is nearly constant (Building confidence)
• 6Identify the orbit (Building confidence)
• 7Why comets are rarely seen (Stretch)
• 8Satellites compared (Stretch)
• 9A complete comparison (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1Direct substitution (Getting started)
• 2Convert the period first (Getting started)
• 3Why 2πr? (Getting started)
• 4A period given in years (Building confidence)
• 5Altitude is not the radius (Building confidence)
• 6Rearrange for the radius (Building confidence)
• 7Find the orbital period (Stretch)
• 8Compare two orbits (Stretch)
• 9Spot the error (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
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• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1Order the stars by temperature (Getting started)
• 2What colour tells you (Getting started)
• 3The Sun's classification (Getting started)
• 4Compare two stars (Building confidence)
• 5Why the order surprises people (Building confidence)
• 6Surface or core? (Building confidence)
• 7Colour is not brightness (Stretch)
• 8Why a cool star can emit a lot (Stretch)
• 9Colour in stellar evolution (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1How a star forms (Getting started)
• 2Why a main sequence star is stable (Getting started)
• 3State the sequence (Getting started)
• 4Becoming a red giant (Building confidence)
• 5Why a red giant is red (Building confidence)
• 6The white dwarf (Building confidence)
• 7The colours of each stage (Stretch)
• 8The balance throughout the life cycle (Stretch)
• 9The Sun's future (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
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• ✓Model answer — 4SD0/1P style

Worked examples (9)

• 1State the sequence (Getting started)
• 2Why a massive star lives a shorter life (Getting started)
• 3The red supergiant (Getting started)
• 4The supernova (Building confidence)
• 5Neutron star or black hole (Building confidence)
• 6Compare the two life cycles (Building confidence)
• 7Where heavy elements come from (Stretch)
• 8What a black hole really is (Stretch)
• 9Mass decides everything (Stretch)

Model answers (9)

• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style
• ✓Model answer — 4SD0/1P style