Grade 8 Science practice sheet

Question 1

What gives the energy that drives the water cycle?

• the Sun
• the Moon
• volcanoes
• wind turbines

Question 2

What is salinity?

• how much salt is dissolved in water
• how deep water is
• how warm water is
• how fast water moves

Question 3

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

Question 4

Which state of matter usually has the lowest density?

• They are all the same.
• solid
• gas
• liquid

Question 5

A force of 80 N pushes on an area of 4 m². What is the pressure in Pa (N/m²)?

answer boxPa

Question 6

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.

Question 7

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.

Question 8

Which has the shortest wavelength?

• infrared
• gamma rays
• visible light
• microwaves

Question 9

Which surface absorbs the most light?

• a white sheet
• polished metal
• a smooth mirror
• a rough, dark surface

Question 10

Farsighted people see far things clearly but have trouble with near things. What kind of lens helps?

• a mirror
• a prism
• a concave lens
• a convex lens