Grade 8 · Science · Unit 1 of 9
Motion, Forces & Newton’s Laws
Speed, velocity, acceleration, friction and the Laws of Motion.
What your child practises
Practises speed, velocity, acceleration, forces, friction, gravity and Newton's three Laws of Motion, with stability. It follows the Grade 8 science skill descriptors on motion and stability and the Laws of Motion in the New Brunswick curriculum.
New Brunswick Curriculum skill descriptor: Scientific Literacy: Investigation, Scientific Literacy: Sensemaking · relationships between variables in motion, stability and the Laws of Motion
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Balanced forces on an object cause…
- no change in its motion
- acceleration
- a turn
- a faster speed
no change in its motion
Hint: A book on a table has balanced forces.
Question 2
Which surface has the least friction?
- gravel
- carpet
- sandpaper
- ice
ice
Hint: Ice is smooth and slippery.
Question 3
What is gravity?
- a light
- a force that pulls objects toward each other
- a force that pushes objects apart
- a type of speed
a force that pulls objects toward each other
Hint: On Earth it pulls objects toward the centre.
Question 4
A car goes at 80 km/h for 3 hours. How far does it travel?
- 27 km
- 83 km
- 240 km
- 160 km
240 km
Hint: Distance = speed × time.
Question 5
What is the difference between speed and velocity?
- velocity includes direction
- they are the same
- speed includes direction
- velocity is slower
velocity includes direction
Hint: 60 km/h north is a velocity.
Question 6
Why do seat belts and airbags protect people?
- they speed up the body
- they remove inertia
- they spread out the force and slow the body gradually
- they stop gravity
they spread out the force and slow the body gradually
Hint: Slowing over a longer time reduces the force.