Grade 8 Science practice sheet
Ontario Curriculum · from Gradelings · Name: ______________________
Question 1
A drone is used to spray crops only where sensors detect pests. How can this technology help the environment?
- It stops all pests forever.
- It can reduce the amount of pesticide used.
- It makes plants need no sunlight.
- It removes the need for any farmers.
Show answer
It can reduce the amount of pesticide used.
Hint: Targeted spraying uses less chemical than covering a whole field.
Question 2
Several tissues working together to do a job make up an…
- organelle
- atom
- organism
- organ
Show answer
organ
Hint: The heart is an organ made of muscle, nerve and other tissues.
Question 3
What are the products of cellular respiration?
- energy, carbon dioxide and water
- glucose and oxygen
- only sugar
- only oxygen
Show answer
energy, carbon dioxide and water
Hint: Cells use glucose and oxygen to release energy, making carbon dioxide and water.
Question 4
Which factor does NOT directly change how fast a liquid flows through a pipe?
- the width of the pipe
- the length of the pipe
- the colour of the liquid
- the viscosity of the liquid
Show answer
the colour of the liquid
Hint: Narrow, long pipes and thick fluids slow flow. Colour does not matter.
Question 5
Which state of matter usually has the lowest density?
- They are all the same.
- solid
- gas
- liquid
Show answer
gas
Hint: Gas particles are very far apart.
Question 6
A force of 80 N pushes on an area of 4 m². What is the pressure in Pa (N/m²)?
answer boxPa
Show answer
20 Pa
Hint: Pressure = force ÷ area.
Question 7
How does the heart act like the pump in a hydraulic system?
- It stores air in tanks.
- It removes all pressure.
- It pushes fluid through a network of tubes.
- It changes the fluid into a solid.
Show answer
It pushes fluid through a network of tubes.
Hint: Both pumps create the pressure that moves a fluid.
Question 8
What is a benefit of hydroelectric power?
- It works without water.
- It never affects ecosystems.
- It makes electricity without burning fuel.
- It is free to build.
Show answer
It makes electricity without burning fuel.
Hint: Operating a dam produces few greenhouse gases, though building it has impacts.
Question 9
For a washing machine, is each item an input or an output?
Sort into: ⬇️ Input · ⬆️ Output
- ✨clean clothes
- 👕dirty clothes
- 🔌electrical energy
- 🌡️waste heat
- 🔊noise
- 🧴laundry soap
- 🪣used soapy water
- 🚿fresh water
Show answer
⬇️ Input: dirty clothes, electrical energy, laundry soap, fresh water · ⬆️ Output: clean clothes, waste heat, noise, used soapy water
Hint: Inputs go into the system. Outputs come out of it.
Question 10
When we say energy dissipates from a machine, we mean it…
- is destroyed
- spreads out as less useful energy, such as heat and sound
- is stored forever
- turns into mass
Show answer
spreads out as less useful energy, such as heat and sound
Hint: Energy is conserved, but it can spread out in forms that are hard to use.
Answer key
- 1. It can reduce the amount of pesticide used. (Think Like a Scientist)
- 2. organ (Cells, Organisms & Technology)
- 3. energy, carbon dioxide and water (Cells & Life Processes)
- 4. the colour of the liquid (Viscosity & Flow)
- 5. gas (Density & Buoyancy)
- 6. 20 Pa (Pressure & Pascal's Law)
- 7. It pushes fluid through a network of tubes. (Hydraulics & Pneumatics)
- 8. It makes electricity without burning fuel. (Fluids, Spills & Society)
- 9. ⬇️ Input: dirty clothes, electrical energy, laundry soap, fresh water · ⬆️ Output: clean clothes, waste heat, noise, used soapy water (Systems in Action)
- 10. spreads out as less useful energy, such as heat and sound (Work, Energy & Efficiency)
Want more than 10 questions?
In Gradelings the questions change every time and adjust to your child, with hints and kind feedback. See all science units.