Points:

• Amount,length,time,luminous intensity, mass, temperature, current are the fundamental physical quantities.
• Same units in every term on either side of =
• When round determining digit is 5 and the truncated digits are 0 then the number is rounded up if the number to remain is odd and truncated if the number to remain is even.
• For ± least decimal places, for */ least significant figure
• 1. Object at uniform motion move with uniform motion unless external force acts on them
  2. $F=\frac{dp}{dt}=\frac{d\left(mv\right)}{dt}$
  3. Each action has an equal and opposite reaction
• The resistance to change in velocity is called inertiait is an old-timey term and is essentially just mass, inertia ∝ mass
• Momentum is "strength of motion"
• Tt can be thought of as how long it takes to stop an object that has a (constant)1 Newton force applied to it
• Momentum is conserved in collisions given that no external forces are acting so it is useful
• Any frame of reference that no acceleration relative to the ground are called inertial frames
• The change in momentum is called impulse, it is the effect of external force on the motion of an object
• Normal force is exerted on by every contact surface
• The weight felt by the person is the normal force by the ground
• If the ground is accelerating like in an elevator then the weight felt by the person will be different

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Trivia:

• $Df\left(x\right)=f\prime \left(x\right)$
• You can move vectors
• Motion of object with respect to another object is relative motion
• When relative velocity is towards the reference point it is called velocity of approach
• Forces are either contact or non-contact
• If you label all forces acting on a body then that diagram is called a free body diagram
• The force normal to the surface exerted by the surface is called normal force
• If a person is not on the ground then they are in free fall
• Free faller feels no force from the floorWeightless