The third chapter from the new CIE A level specification, regarding dynamics. Written by a Cambridge offer-holder and A*A*A* predicted student. Hand-drawn diagrams and detailing included.
Dynamics
Mass = quantity of matter; measure of the inertia of an object to changes in velocity
Newton’s First Law
An object remains at rest or travelling at a constant velocity unless a resultant force is
applied
Newton’s Second Law
dp
F= is the actual form of NL2 where p is momentum, and momentum is equal to the
dt
product of mass and velocity
F=ma is only true where the mass is constant
In words, we can write either resultant force is equal to the rate of change of momentum or
resultant force on an object is proportional to the mass of the object and its acceleration in
the same direction as the force
This law leads to NL1
Newton’s Third Law
Force of body A on body B is equal in magnitude and opposite in direction to the force
exerted by body B on A
These forces are of the same kind
Momentum and Newton’s Laws Summarised
Newton’s Second Law or NL2 can be used to state F=ma and solve in various scenarios
Note the definition of force is rate of change of momentum
Weight = the effect of a gravitational field on a mass
Weight = mass x acceleration of free fall
Non-Uniform Motion
Drag increases as speed increases
Hence as an object is falling, the drag will increase until it is equal to the object’s weight
Hence the object will be in equilibrium, moving at a constant terminal velocity
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller saanyav. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £6.99. You're not tied to anything after your purchase.