Chapter P4 - Explaining Motion

Overview

• Describing motion - speed, velocity, acceleration, distance-time graphs, speed-time graphs; displacement-time graphs, velocity-time graphs.
• Forces - Newton's laws, interaction pairs, resultant forces, how forces affect motion, momentum
• Work and energy - work done, gravitational potential energy, kinetic energy

Revision

• download legacy course checklist, download new course checklist
• legacy Bitesize P4 revision page, new course Bitesize P4 revision page
• Click here for my StudyStack activities on Explaining Motion.
• Download Names of Forces Sheet. These are the names of forces that are commonly used in the exams. Practise using these words so you can understand exactly what a question means and so you can correctly describe the forces in a situation. Try this Names of Forces Quiz.
• Interaction Pairs Quiz - check your understanding of Newton's Third Law.
• Buoancy forces - Visualise the buoyancy and weight force on an object in a fluid.

Measuring Speed and Distance Time Graphs

• Click here for my some excellent powerpoints on forces and motion from Staffordshire Learning Net.
• Click here for Usain Bolt's 100m Beijing world record on youtube.
• Click here for PheT's Moving Man simulation - to explore displacement-time and velocity-time graphs.

Newton's Three Laws of Motion

1. An object will not accelerate (speed up, slow down or change direction) if there is NO resultant force on it.
2. If an object experiences a resultant force, then it accelerates - its acceleration is proportional to the force and inversely proportional to the mass of the object.
3. Forces come in pairs - if A exerts a force on B in one direction, then B exerts a force on A in the opposite direction; the force is the same size and the same type.

Physics Tracker Software

Click here to download "Physics Tracker" software. I use this to analyse regular and high speed video of experiments we do in class.