Motion Basics
How do you know something is moving?
Its position changes with time.
What does each dot in a particle model represent?
The object’s position at a specific time.
Define scalar.
Quantity with magnitude only.
What is the 'origin' in a coordinate system?
The point where position = 0.
What is on the x-axis of a position–time graph?
Time.
Name one type of motion other than straight-line motion.
Circular, vibration, back-and-forth.
What would a particle model of a parked car look like?
A: Dots all at the same place.
Define vector.
Quantity with magnitude and direction.
If a runner moves from 0 m to 5 m east, what is their displacement?
A: +5 m east.
What is on the y-axis of a position–time graph?
Position.
What two things are always part of describing motion?
Place (position) and time.
What does the spacing between dots in a motion diagram tell us?
The speed (close = slow, far apart = fast).
Give an example of a scalar.
Distance, time, mass, temperature.
If a runner moves 10 m east and 10 m west, what is total distance and displacement?
Distance = 20 m, displacement = 0.
What does the slope of a position–time graph represent?
Velocity.
Give a real-life example of motion you see every day.
Walking, cars, clocks, etc.
Which is simpler: motion diagram or particle model? Why?
Particle model; it reduces objects to dots.
Give an example of a vector.
Displacement, velocity, force.
What symbol is used for displacement?
Δx.
If two lines cross on a position–time graph, what does it mean?
The two objects are at the same place at the same time.
What is the difference between motion diagram and particle model?
Motion diagram shows positions at intervals; particle model replaces object with dots.
How could you represent a bouncing ball in a motion diagram?
Dots up and down, changing direction.
Which is a vector: speed or velocity? Why?
Velocity, because it includes direction.
Two vectors: 3 m east + 5 m west. What is the resultant displacement?
-2 m West
A runner is at 2 m at 0 s, and at 10 m at 4 s. What is their velocity?
(10–2) ÷ (4–0) = 2 m/s.