What is distance?
Distance is how far an object moves. It is a scalar quantity (no direction).
What is displacement?
Displacement is a vector; it includes distance and direction from start to finish point.
What is the formula for speed?
Speed = distance ÷ time (v = s ÷ t)
How do you calculate average speed?
Average speed = total distance travelled ÷ total time taken
What are some typical average speeds?
Walking ≈ 1.5 m/s, Running ≈ 3 m/s, Cycling ≈ 6 m/s
What is the speed of sound in air?
Speed of sound in air ≈ 330 m/s
What is velocity?
Velocity is speed in a given direction. It is a vector quantity.
When does velocity change?
Velocity changes if speed or direction changes (even if speed stays constant).
What is acceleration?
Acceleration is the change in velocity per second. It is a vector.
What is the formula for acceleration?
Acceleration = change in velocity ÷ time (a = Δv ÷ t)
What is the acceleration due to gravity near Earth?
About 9.8 m/s²
What is uniform acceleration?
Acceleration that stays constant.
What is the equation for uniform acceleration?
v² - u² = 2as
What does the gradient of a distance-time graph show?
The object’s speed.
What does a straight line mean on a distance-time graph?
Constant speed.
What does an upwards curve show on a distance-time graph?
Accelerating.
What does a downwards curve show on a distance-time graph?
Reducing speed.
What does a horizontal line show on a distance-time graph?
The object is stopped.
What does the gradient of a velocity-time graph show?
The object’s acceleration.
What does a straight line mean on a velocity-time graph?
Constant acceleration.
What does a curved line mean on a velocity-time graph?
Changing acceleration.
What does a horizontal line mean on a velocity-time graph?
Constant velocity.
What is a drag force?
A frictional force from a fluid (liquid or gas) that acts against motion.
How does drag force change with speed?
It increases as speed increases.
