Kinematics lessons for AQA GCSE Physics

In the AQA GCSE syllabus

1. Lesson 4Scalars vs Vectors

   Current has a direction, so why is it a scalar?

   Syllabus details

   Syllabus: 4.5.1.1 Scalar and vector quantities; 4.5.6.1.3 Velocity (explain the vector-scalar distinction as it applies to displacement, distance, velocity and speed)

2. Lesson 5Distance vs Displacement

   Run a full lap on a 400 m track: is your displacement 400 m or 0?

   Syllabus details

   Syllabus: 4.5.6.1.1 Distance and displacement

3. Lesson 9What Is Acceleration? Why It's 180, Not 20

   You gain 30 points in 120 days, your friend gains 10 points in 10 days. Who improved faster?

   Syllabus details

   Syllabus: 4.5.6.1.5 Acceleration (a = Δv/t; acceleration from the gradient of a velocity-time graph; v^2 - u^2 = 2as for uniform acceleration)

Partly in the syllabus

Only part of the lesson is in the syllabus. Each lesson says which part.

1. Lesson 6Average Speed vs Average Velocity vs Instantaneous Velocity

   Two taxi rides to the same place: 7.5 km in 14 min, or 10 km in 15 min. Which one is faster?

   Syllabus details

   Syllabus: 4.5.6.1.2 Speed (calculate average speed for non-uniform motion); 4.5.6.1.3 Velocity (velocity is speed in a given direction); 4.5.6.1.4 The distance-time relationship (HT only: speed at a particular time from a tangent)

   In it: Average speed, velocity, and finding speed at one instant from a tangent (Higher tier only) are listed. Not in it: Average velocity and instantaneous velocity are not named, so the three-way comparison is not tested directly.

2. Lesson 7How to Find Average Velocity of a Multi-Part Trip

   A car covers 1/4 of the trip at 20 m/s and the rest at speed v. The whole-trip average velocity is 16 m/s. What is v?

   Syllabus details

   Syllabus: 4.5.6.1.2 Speed (students should be able to calculate average speed for non-uniform motion)

   In it: Calculating average speed for motion with changing speed is listed, which is the method for a trip in several parts. Not in it: Average velocity (total displacement divided by total time) is not listed, only average speed.

3. Lesson 8How to Find Change in Velocity: Why It's 7, Not 3

   A ball hits the ground at 5 m/s and bounces up at 2 m/s. Is its change in velocity 3 m/s or 7 m/s?

   Syllabus details

   Syllabus: 4.5.6.1.5 Acceleration (acceleration = change in velocity / time taken, a = Δv/t)

   In it: Change in velocity appears inside the equation for average acceleration, which students recall and apply. Not in it: Finding Δv with signs and direction, such as a ball bouncing back, has no entry of its own.

4. Lesson 10Speeding Up or Slowing Down? Check a and v

   A car's acceleration keeps getting smaller. Is it speeding up or slowing down?

   Syllabus details

   Syllabus: 4.5.6.1.5 Acceleration ('An object that slows down is decelerating'; interpret lines and slopes of velocity-time graphs to determine acceleration)

   In it: Slowing down is called decelerating, and acceleration is read from velocity-time graph slopes. Not in it: The rule that a and v in the same direction mean speeding up, opposite means slowing down, is not stated.

Not listed as a separate topic

These are basic ideas that the later lessons build on, so they are still worth watching first.

1. Lesson 1Point Mass (Particle) Explained

   Can a walking cat be treated as a particle?

2. Lesson 2Frame of Reference & Coordinate System

   Sitting still on a speeding subway: are you moving or not?

3. Lesson 3Instant vs Time Interval

   Is "the 3rd second" a moment or a stretch of time?