PSLE Science Physics Topics 3 — Questions and Answers
Question 1: How does sound travel?
- Through light waves
- Through vibrations in a medium (Correct answer)
- Through electric current
- Only through air
Correct answer: Through vibrations in a medium
Sound travels through vibrations that pass through a medium (solid, liquid, or gas). It cannot travel through a vacuum.
Question 2: Which of the following objects would be attracted to a magnet?
- Wooden ruler
- Plastic comb
- Steel paper clip (Correct answer)
- Glass marble
Correct answer: Steel paper clip
Steel is a magnetic material (it contains iron) and would be attracted to a magnet. Wood, plastic, and glass are not magnetic.
Question 3: What is the process called when a liquid changes to a gas?
- Melting
- Freezing
- Evaporation (Correct answer)
- Condensation
Correct answer: Evaporation
Evaporation is when a liquid changes to a gas, usually at the surface of the liquid. When heated to boiling point, it is called boiling.
Question 4: What does a thermometer measure?
- Mass
- Volume
- Temperature (Correct answer)
- Force
Correct answer: Temperature
A thermometer measures temperature, which indicates how hot or cold something is.
Question 5: Which of the following is a non-renewable source of energy?
- Solar energy
- Wind energy
- Coal (Correct answer)
- Hydroelectric energy
Correct answer: Coal
Coal is a non-renewable energy source — it takes millions of years to form and will eventually run out.
Question 6: In which direction does heat naturally flow?
- From cold to hot objects
- From hot to cold objects (Correct answer)
- In all directions equally regardless of temperature
- Only downward
Correct answer: From hot to cold objects
Heat naturally flows from hotter objects to cooler objects until thermal equilibrium is reached.
PSLE Science Physics Topics 3
How does sound travel?