Dynamics Flashcards
What is a force
Newton’s first law
A body will remain stationary or in continuous linear motion unless acted on by a resultant force
How to use this law : FR=0, the thing will do what ever it was initially doing like staying still or move at whatever speed
So when the forces cancel out cause left hand and right hand same force then nothing will happen
Newton second law
F = ma
So if anything unknown, just find the rest that is known and find the unknown
Newtons 3rd law
For every action, there is equal and opposite reaction
Conditions to be a action reaction pair:
- act on different objects
- same magnitude
- opposite direction
- same type of force
Friction , definition and what is it
Friction is the contact force which opposes motion between surfaces in contact
Advantages and disadvantages of friction and how to overcome it
Friction will act in the direction opposite to motion
Adv
- walking on roads
- friction in brake pads and wheels of cars and bicycles
Disadvantage
- wear down moving parts
- more energy needed to overcome or maintain constant speed as compared to smooth surface
- wear and tear
How to overcome
- use lubricant
- use ball bearings between moving surfaces
- make sure the moving parts in the machinery has very smooth surfaces
How to solve
