forces
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what is force?
a force is a push or pull between two objects
what are the two groups of forces?
• non contact forcs • contact forces
what is non contact force?
where two objects are seperate but stll exert a force on eachother regardless
what is contact force?
where two objects involved are phisically touching eachother
what are the examples of contact forces?
• push • pull • air resistance • water resistance • friction
what are the examples of non contact forces?
• magnetic force • electrostatic force • weight (friction)
what is ‘drag’?
water and air resistance can collectivelty be called ‘drag’
what is gravity?
the name of the fundamental force that all objects with mass (or energy) to attract eachother
what is an object’s weight on earth?
its the name of the force that acts on the object due to earth’s gravitational field. i always acts towards the center of the earth.
what unit is force measured in?
newtons
how do you measure force?
newton meter
what is newton’s 1st law of motion?
a body remains at rest, or in motion at a constant speed in a straight line, unless acted upon by a force.
what is newton’s 2nd law of motion?
if a body is acted upon by a force, the object will accelerate i.e. it’s speed or direction will change
what is a free body diagram?
it’s a way of showing the forces acting on an object.
what is the resultant force?
it’s the sum of all the forces on an object. it’s the overall effect if the pushes and pulls on an object.
what is the resultat force of an object if all the forces are balanced?
zero
what is newton’s 3rd law of motion?
whenver one body exerts a force on a second body, the second body exerts a force that is equal in magnitude and opposite in the direction on the first body i.e. evey action has and equal and opposite reaction
what eqation can also represent newton’s second law?
F=ma