Every card in Space and gravity, Year 8: more practice
The whole deck, in order — so you can read it through before your child ever sees it.
- At new Moon, why can we not see the Moon?
Its lit half faces away from the Earth
HintThe Moon is still there; think about which side the Sun lights.
WhyAt new Moon, the Moon is between the Earth and the Sun, so the sunlit half faces away from us.
- At full Moon, why does the Moon look like a complete bright circle?
The whole of its lit half faces the Earth
HintThink about where the Moon is in its orbit.
WhyAt full Moon, the Moon is on the far side of the Earth from the Sun, so we look at the whole sunlit half.
- About how long is it from one full Moon to the next?
About a month (29.5 days)
HintCount the cycle of phases on a calendar.
WhyThe cycle of phases takes about 29.5 days.
- For a lunar eclipse, which body is between the other two?
The Earth
HintThe body we live on blocks the Sun's light from reaching the Moon.
WhyIn a lunar eclipse the Sun, Earth and Moon are in a line with the Earth in the middle. The Moon is in the Earth's shadow.
- Which instrument measures mass: a balance or a newtonmeter?
A balance
HintOne measures kilograms.
WhyA balance compares masses and gives kg. A newtonmeter measures a force, weight, in newtons.
- An astronaut weighs less on the Moon than on Earth. Why?
The Moon's gravity is weaker
HintWeight depends on the pull of the body you stand on.
WhyThe Moon is smaller than the Earth, so its gravitational field strength is lower, so the same mass is pulled less. Mass is unchanged.
- Weight is a force. In which direction does it act on an object on Earth?
Towards the centre of the Earth
HintWhich way would an object fall?
WhyWeight is the pull of gravity, so it acts downwards towards the centre of the Earth.
- On Earth, g = 10 N/kg. What is the weight of an 8 kg object in newtons? (number only)
80
HintW = m × g.
Why8 × 10 = 80 N.
- On the Moon g = 1.6 N/kg. A rock has a mass of 50 kg. What is its weight there in newtons? (number only)
80
HintW = m × g.
Why50 × 1.6 = 80 N. On Earth the same rock weighs about 500 N.
- A box weighs 240 N where g = 10 N/kg. What is its mass in kilograms? (number only)
24
HintRearrange W = m × g.
Whym = W ÷ g = 240 ÷ 10 = 24 kg.
1★ KS3-PHYS-SPA-0038
2★ KS3-PHYS-SPA-0039
3★ KS3-PHYS-SPA-0040
4★ KS3-PHYS-SPA-0041
5★ KS3-PHYS-SPA-0042
6★ KS3-PHYS-SPA-0043
7★ KS3-PHYS-SPA-0044
8★ KS3-PHYS-SPA-0045
9★ KS3-PHYS-SPA-0046
10★ KS3-PHYS-SPA-0047
Keep what you learn
Here, nothing is saved. In your child’s own sky every card is scheduled — it comes back just before they’d forget it — and the professor who wrote it is one tap away.