Motion, Momentum & Impulse
Everything in the universe is in motion, and there are basic laws of mechanics that govern this.
Velocity is the rate of change of an object's position, and therefore has direction. This makes it a vector quantity, unlike speed which is scalar (magnitude but no direction).
velocity = distance / time
The units of velocity are m/s
Acceleration is the rate of change of velocity, and so is the mathematical derivative of this.
acceleration = change in velocity / change in time
The units of acceleration are m/s²
We can plot motion on two main types of graph - it is important to know the properties of each.
The Gradient is the velocity - draw a tangent to find the instantaneous velocity
Horizontal line represents zero velocity
The Gradient is the acceleration
The Area beneath the graph is the displacement
When acceleration is constant (e.g. free fall when we ignore air resistance), we can use SUVAT equations to work out the variables:
Linear motion can be investigated with trolley cars, air gliders, ticker tape, light gates, data loggers and motion capture.