Physics

Lessons

1. 01

   Units and measurement

   Physics is measured quantities with units. Convert carefully, check dimensions, and report results with sensible precision.

2. 02

   Vectors and motion

   Describe motion with position, velocity and acceleration as vectors; with constant acceleration, four equations predict everything, and horizontal and vertical motions are independent.

3. 03

   Relative motion and reference frames

   Every velocity is measured relative to an observer. Name the frame, then add velocities as vectors: v_A/C = v_A/B + v_B/C.

4. 04

   Newton laws and force diagrams

   Forces change motion. Isolate one object, draw every force acting on it, and apply ΣF = ma along each axis.

5. 05

   Friction and inclined surfaces

   Friction is the contact force along a surface. Static friction adjusts up to a limit; kinetic friction has a fixed size, μₖN, and opposes sliding.

6. 06

   Work energy and power

   Work transfers energy. Kinetic and potential energy trade places, and the total is conserved unless friction or other forces add or remove energy. Power is the rate of energy transfer.

7. 07

   Impulse and momentum

   Momentum p = mv is a vector. A force acting for a time changes it (impulse). In a collision with no external force, total momentum is conserved.

8. 08

   Circular motion

   An object moving in a circle at constant speed is accelerating towards the centre, a = v²/r. Some real force (tension, friction, gravity, normal force) must supply the net inward force mv²/r.

9. 09

   Laboratory graphs and evidence

   Plot measured data, draw the best straight line, and read physics from its slope and intercept — with units and a realistic uncertainty.