Year 6 Science · Light travels in straight lines · Test yourself
Year 6 Science Light travels in straight lines: check-up and practice test questions
Part of the Year 6 Science light travels in straight lines chapter. Chapter overview · whole chapter on one page
Exercise 7Z Check-up
1
Does light appear to travel in a straight line? Write yes or no.
yes
Method. Recall the idea.
- Recall. Light appears to travel in straight lines.straight lines
- Write the answer. yes
Check. Holes in a line let light through. ✓
2
What is a straight line of light with an arrow called? Write the word.
ray
Method. Recall the definition.
- Recall. A straight line with an arrow is a ray.ray
- Write the answer. ray
Check. Rays show the direction of light. ✓
3
Why is a shadow the same shape as the object that makes it? Write one word.
straight
Method. Recall the reason.
- Recall. Light travels in straight lines and is blocked by the edges.straight lines
- Write the answer. straight
Check. Light cannot bend round the object. ✓
4
On which side of an object is its shadow: towards the light, or away from it? Write the words.
away from the light
Method. Recall the position.
- Recall. The object blocks the light on the side away from the light source.away
- Write the answer. away from the light
Check. The side facing the light is lit. ✓
5
Look at the table in section 7.3. What is the shadow height at 20 cm? Write the number of centimetres.
30 cm
Method. Read the table.
- Read the row. The row for 20 cm gives a shadow height of 30 cm.30 cm
- Write the answer. 30 cm
Check. The nearest card makes the biggest shadow. ✓
6
Look at the table in section 7.3. Which distance gives a shadow of 5 cm? Write the distance in centimetres.
120 cm
Method. Read the table.
- Read the row. The shadow of 5 cm is at 120 cm.120 cm
- Write the answer. 120 cm
Check. The furthest card gives the smallest shadow. ✓
7
When an object is moved nearer the light, does its shadow get bigger or smaller? Write the word.
bigger
Method. Recall the pattern.
- Recall. A nearer object blocks more of the spreading light, so its shadow is bigger.bigger
- Write the answer. bigger
Check. The table shows this pattern. ✓
8
In a pinhole camera, is the image upside down or upright? Write the words.
upside down
Method. Recall the pinhole rule.
- Recall. Light from the top of the object lands at the bottom of the screen.bottom
- Write the answer. upside down
Check. Straight rays cross at the hole. ✓
9
Name the object that blocks light to make a shadow, and say whether it is opaque or transparent. Write one word: opaque or transparent.
opaque
Method. Recall the definitions.
- Recall. An opaque object blocks light, so it makes a shadow.opaque
- Write the answer. opaque
Check. A transparent object lets light through. ✓
10
Explain why it is not safe to look at the Sun, even through sunglasses. Write one sentence.
Accept any sentence that says the Sun is very bright, and sunglasses do not stop its light from damaging the eyes.
Method. Think about the Sun.
- Think about the light. The Sun is very bright, and its light can damage the eyes.damage
- Think about sunglasses. Sunglasses do not make the Sun safe to look at.not safe
- Write the answer. Accept any sentence that says the Sun is very bright, and sunglasses do not stop its light from damaging the eyes.
Check. Never look at the Sun. ✓
Total 16 marks. Allow about 16 minutes.
Exercise 7X Practice test questions
1
FA card with a hole is placed between a torch and a wall. The light reaches the wall through the hole. Write one word that describes the path of the light.[1 mark]
straight
Method. Think about the path of light.
- Think about the path. Light travels in straight lines, so its path through the hole is straight.straight
- Write the answer. straight
Check. Light appears to travel in straight lines. ✓
2
RA torch shines on a card arrow, and the shadow on the wall is an arrow shape. Explain why the shadow has the same shape as the card. Write one sentence.[2 marks]
Accept any sentence that says light travels in straight lines, and is blocked by the edges of the arrow, so the shadow copies its outline.
Method. Use the straight line idea.
- Think about the light. Light travels in straight lines past the edges of the arrow.straight lines
- Think about the shadow. The light blocked by the edges makes the shadow copy the outline.copy the outline
- Write the answer. Accept any sentence that says light travels in straight lines, and is blocked by the edges of the arrow, so the shadow copies its outline.
Check. The outline of the object is copied. ✓
3
FThe table shows shadow heights: a card 20 cm from a torch casts a shadow of 30 cm; at 40 cm it casts 15 cm; at 60 cm it casts 10 cm; at 120 cm it casts 5 cm. Write the distance at which the shadow is 10 cm tall.[1 mark]
60 cm
Method. Find the 10 cm shadow.
- Read the table. The shadow of 10 cm is at a distance of 60 cm.60 cm
- Write the answer. 60 cm
Check. Nearer objects make bigger shadows. ✓
4
PSUsing the same table: the card moves from 20 cm to 120 cm from the torch. By how many centimetres does the shadow height fall? Write the number.[2 marks]
25 cm
Method. Subtract the shadow heights.
- Read the heights. The shadow is 30 cm at 20 cm, and 5 cm at 120 cm.30 and 5
- Subtract. The fall is 30 minus 5.30 - 5 = 25
- Write the answer. 25 cm
Check. 5 + 25 = 30. ✓
5
RExplain why a shadow gets bigger when the object is moved nearer the torch. Write one sentence.[2 marks]
Accept any sentence that says light spreads out from the torch in straight lines, so a nearer object blocks more of it and gives a bigger shadow.
Method. Think about the spread of light.
- Think about the light. Light spreads out in straight lines from the torch.spreads out
- Think about the shadow. A nearer object blocks a wider spread, so its shadow is bigger.bigger
- Write the answer. Accept any sentence that says light spreads out from the torch in straight lines, so a nearer object blocks more of it and gives a bigger shadow.
Check. The table supports this. ✓
6
FIn a pinhole camera, light from the top of a tree lands at which part of the screen? Write the word: top or bottom.[1 mark]
bottom
Method. Follow the straight line.
- Follow the ray. The ray from the top of the object crosses the hole and lands low on the screen.bottom
- Write the answer. bottom
Check. The image is upside down. ✓
7
RExplain why the image in a pinhole camera is upside down. Write one sentence.[2 marks]
Accept any sentence that says light from the top of the object travels in a straight line through the hole to the bottom of the screen.
Method. Think about straight rays.
- Think about the top. Light from the top goes straight through the hole, and lands at the bottom.bottom
- Think about the bottom. Light from the bottom lands at the top, so the image is reversed.reversed
- Write the answer. Accept any sentence that says light from the top of the object travels in a straight line through the hole to the bottom of the screen.
Check. Straight rays cross at the hole. ✓
8
RA student says: “I can look at the Sun through a pinhole camera, because the hole makes it safe.” Explain why the student is not right. Write one sentence.[2 marks]
Accept any sentence that says the Sun is very bright, and the light through a pinhole can still damage the eyes, so it must never be looked at.
Method. Check the safety rule.
- Check the rule. The Sun must never be looked at, even through a pinhole.never
- Give the reason. The light is still very bright and can damage the eyes.damage
- Write the answer. Accept any sentence that says the Sun is very bright, and the light through a pinhole can still damage the eyes, so it must never be looked at.
Check. A pinhole does not make the Sun safe. ✓
9
FWrite one safety rule for using a torch. Write one sentence.[1 mark]
Accept any rule that says never shine a torch into someone's eyes, or keep the beam away from people's eyes.
Method. Read the table.
- Read the table. The table says to keep the torch beam away from people's eyes.away from eyes
- Write the answer. Accept any rule that says never shine a torch into someone's eyes, or keep the beam away from people's eyes.
Check. A bright beam can hurt the eyes. ✓
10
PSRuby moves a card from 40 cm to 60 cm away from a torch, and says the shadow must be bigger. Is Ruby right? Write yes or no, and give the reason in one word.[2 marks]
no; smaller
Method. Read the table.
- Read the table. At 40 cm the shadow is 15 cm, and at 60 cm it is 10 cm.15 and 10
- Decide. The shadow gets smaller when the card is further away, so Ruby is not right.smaller
- Write the answer. no; smaller
Check. Further from the light means a smaller shadow. ✓