Page 29 - Genius PBD Science Year 4

P. 29

Science Year 4 Answers

(c) (i) and (iii) (c) Increases
5.3 Refraction of Light
4. (a) Sonar 2. (a) Response to touch
5. (a) Light is refracted when it (b) Ultrasound (b) (i) Gravitational pull
moves from water to air. This (c) Echo (ii) Sunlight
causes the image of a straw 5. (a) Noise pollution makes (c) The root of the plant always
to appear lifted and bent. it difficult for humans to grows downwards because
(b) Light can be refracted communicate, causes hearing of the gravitational pull.
(c) The formation of rainbows problems, disturbs peace 3. (a) Moving the hand away
(d) Rainbows are caused by of mind as well as causes spontaneously as it touches a
the refraction of sunlight by emotional stress. thorn.
raindrops. (b) (i) Build a solid barriers (b) Skin
6. Pupil’s answer (ii) Use sound absorbing (c) The boy’s hand will be hurt.
material (d) To prevent injuries.
(c) Uses of sound: (e) Listening to the radio at a
SUMMATIVE PRACTICE 5 Communication, emergency very high volume; Directing
alert, notification, light to the eyes (accept any
Objective Questions entertainment (i-Think circle other correct answer)
map) 4. (a) Photosynthesis
1. A 2. D 3. D 4. A 5. C (b) Carbon dioxide + Water,
6. B 7. A 8. B
Glucose + Oxygen
SUMMATIVE PRACTICE 6 (c) X is the chlorophyll that
Subjective Questions
is found on plants and
1. (a) This tool reflects light to Objective Questions it absorbs sunlight for
parts of the teeth that are 1. C 2. B 3. D 4. D 5. D photosynthesis.
difficult to be seen and 6. C 7. A 8. D 9. D (d) Because plants cannot move
makes the process of dental to find food.
examinations easier. 5. (a) Periscope
(b) Periscope/ Car’s side mirrors Subjective Questions (b) This device is used to observe
(c) (i) Mirrors (a) Sound travels in all directions. conditions on the surface
(ii) Aluminium foil (b) The sound of a fire engine of the sea from inside a
2. (a) Light moves in a straight line. siren gave an emergency submarine.
(b) The distance between the signal to other drivers on the (c) The mirrors in the periscope
source of light and the object. road to give an emergency reflect light and enable
(c) route to the fire engine. humans to see the surface of
(c) (i) Can cause hearing the sea.
problem (d) Mirror / Dental mirror
(ii) Can cause disturbance (e)
(d) Reduce the distance between and stress
the object and the source of (d) Using a device that can Light hitting Light bouncing
the mirror
off the mirror
light. absorb sound / Build solid
barrier
UNIT 6 Sound
6.1 Sound
MID-YEAR ASSESSMENT Surface of a mirror
1. (a) Bowing
(b) Plucking Objective Questions UNIT 7 Energy
(c) Knocking 1. B 2. C 3. B 4. B 5. D
(d) Blowing 6. A 7. C 8. C 9. C 10. D 7.1 Energy
(e) Clapping 11. B 12. C 13. A 14. C 15. B 1. (a) Energy is the ability to do
(f) Beating 16. A 17. A 18. C 19. D 20. C work.
(g) Knocking 21. B 22. B 23. D 24. D 25. B
(h) Clapping (b) (i) Wind
(i) Beating Subjective Questions (ii) Water
2. Sound is produced by vibrations. (iii) Sun
(iv) Food
3. (a) P, Q and R can hear the 1. (a) (i) Low (v) Fossil fuels
sirens of the fire engine. (ii) High
(b) Sound travels in all directions. (b) Because his lungs need to (vi) Nuclear
take in more oxygen. (vii) Waves

13 Jawapan Genius PBD SCIENCE YR4.indd 4 19/10/2022 5:13 PM

24 25 26 27 28 29 30