Topic
Forces in Action
This unit examines the effects of forces on objects, covering equilibrium, dynamics, and pressure. Explore how to represent forces visually with free‑body diagrams, calculate moments and torque, and apply principles like Archimedes’ buoyancy rule.
Why Forces Matter
in Physics
The ancient Greeks believed there were two fundamental forces – an attractive force they named “love” and a repulsive force they named “strife”. Our current understanding is that there are four forces of nature: the electromagnetic (it turns out electrostatic and magnetic are really the same thing) and gravitational are the most noticeable, as these dictate our everyday interactions. However, holding the nucleus together are the strong and weak nuclear forces that are only felt on length scales unfamiliar to us.
Forces tell us how things interact and will allow us to determine how the universe will evolve, how to build skyscrapers and faster or more efficient vehicles. They even tell electrons how to move in computer chips. However, much is still unknown – why is gravity so much weaker than the other three? If gravity is only attractive, why is the expansion of the universe accelerating?
Core Concepts
Force, Mass & Weight
Centre of Mass
Free‑Body Diagrams
Drag & Terminal Velocity
Force, mass and weight
Blurb coming soon
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.13 Resultant Force and Acceleration
GCSE Ch2.13A Additional Resultant Force and Acceleration
A nice simulation from PhET:
I think these are fab, and hopefully your school has a subscription to them.
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Centre of Mass
Blurb coming soon
2.2.3 Centre of Mass
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.13 Resultant Force and Acceleration
GCSE Ch2.13A Additional Resultant Force and Acceleration
A nice simulation from PhET:
I think these are fab, and hopefully your school has a subscription to them.
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Free-body diagrams
Blurb coming soon
2.2.1 Dynamics
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.13 Resultant Force and Acceleration
GCSE Ch2.13A Additional Resultant Force and Acceleration
A nice simulation from PhET:
I think these are fab, and hopefully your school has a subscription to them.
123: Understanding frictional forces
124: Forces on static structures
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Drag and terminal velocity
Blurb coming soon
2.1.7 Friction
2.1.8 Terminal Velocity
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.14 Terminal Velocity
A nice simulation from PhET:
I think these are fab, and hopefully your school has a subscription to them.
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Moments and equilibrium
Blurb coming soon
2.2.2 Moments
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.16. Moments, Turning and Balancing
I think these are fab, and hopefully your school has a subscription to them.
004: Moments and equilibrium
180: Moments
324: Balanced Forces
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Couples and torque
Blurb coming soon
2.2.2 Moments
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
B5. Moments
I think these are fab, and hopefully your school has a subscription to them.
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Triangle of forces
Blurb coming soon
2.2.5 Equilibrium
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
B5. Moments
A nice simulation from PhET: Vector Addition
I think these are fab, and hopefully your school has a subscription to them.
164: Triangles and parallelograms of forces
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Density and pressure
Blurb coming soon
2.2.6 Density & Pressure
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
I think these are fab, and hopefully your school has a subscription to them.
064: Understanding and using pressure
260: Displacement, Upthrust and Archimedes’ Principle
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Archimedes’ principle
Blurb coming soon
2.2.6 Density & Pressure
Lewis Matheson has taken the specification and turned it into a bite-size student-friendly format. I recommend printing this out and having a learning checklist at the start of your folder for each section:
OCR A – module 3 – forces
AQA – module 4 – mechanics and materials
Sign up for a free account to Isaac Science and it’ll save and track your progress – working through these problems is necessary to secure that 30-40% of the paper that will be mathsy.
GCSE Ch2.17 Pressure, Hydraulic Systems and Depth
GCSE Ch2.17A Additional Pressure, Hydraulic Systems and Depth
A nice simulation from PhET: Under pressure
I think these are fab, and hopefully your school has a subscription to them.
See below for a quick selection of the relevant videos, you can find Lewis’ full playlist for forces in action here.
Let’s Learn Together!
If you’ve fallen out of love with Physics; you’re struggling with the mathematical nature of the subject; you’re not sure how to revise effectively or demonstrate your knowledge when it comes to exams; you really need to secure a top grade to get into your dream university or next step. It’s time to get in touch and get you back on track!
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