Study Notes
Movement and position in physics involve understanding how objects change their location over time, described using terms like speed, velocity, and acceleration.
- Speed — distance travelled per unit time Example: A car moving at 60 km/h.
- Velocity — change of displacement per unit time, containing both direction and magnitude Example: A plane flying north at 500 km/h.
- Acceleration — rate of change of velocity Example: A car increasing its speed from 0 to 60 km/h in 10 seconds.
- Deceleration — a decrease or negative change in speed or velocity Example: A bike slowing down from 20 km/h to a stop.
- Speed-time Graphs — graphical representation where the gradient is acceleration, and the area under the line is the distance travelled Example: A straight line indicates constant acceleration.
- Distance-time Graphs — graphical representation where the gradient is velocity Example: A flat line indicates the object is stationary.
- Uniform Acceleration Equation — (final speed)^2 = (initial speed)^2 + 2 × acceleration × distance moved Example: Used to find final speed when initial speed, acceleration, and distance are known.
Exam Tips
Key Definitions to Remember
- Speed: distance travelled per unit time
- Velocity: change of displacement per unit time
- Acceleration: rate of change of velocity
Common Confusions
- Confusing speed with velocity, which includes direction
- Misinterpreting deceleration as acceleration
Typical Exam Questions
- What does the gradient of a speed-time graph represent? Acceleration
- How do you calculate the distance travelled from a speed-time graph? By finding the area under the line
- What does a horizontal line on a distance-time graph indicate? The object is stationary
What Examiners Usually Test
- Understanding of the difference between scalar and vector quantities
- Ability to interpret and analyze graphs related to motion