20180305 - Dynamics - the reasons for motion
Monday, 5 March 2018
11:11 AM
Dynamics - the reasons for motion
Newton's Laws of Physics
- Every body persists in its state of rest or of uniform motion in a straight line, until it is compelled to change that state by forces impressed on it.
- In inertial frames
- For every action there is always an opposing equal action
- The mutual actions of two bodies upon each other are always equal and directed to each other
- Forces always occur in symmetrical pairs
- Forces come in
symmetric pairs that add to zero
Note - The total internal forces in a system is zero.
Units
A litre of milk is around 10N
Water in a pool of volume 50x10x2m at p=1000kgm-3 is
around 10MN
The maximum force a human can exert with its feet is around 2kN