3.2 - forces in action Flashcards
what is a tension force
a force experienced by a wire or rope when it is stretched. eg rubber band
what is contact force
a force exerted when 2 objects touch
what is weight caused by
gravity
what is friction
a restive force between 2 objects
when is f=ma applicable
when mass is constant
what is newtons second law
the force applied on an object is directly proportional to the momentum
what is the equation of weight
weight = mass × gravity (w=mg)
if a force is at an angle what do you have to do to it to calculate it
resolve it (either to the horizontal and vertical or parallel and perpendicular)
to calculate forces what is drawn?
a free body diagram
what is acceleration due to gravity known as (letter and number)
g and -9.81 or 9.81
what is weight (definitely)
the force experienced by any mass in a gravitational field
what is balanced forces (resultant force)
the forces acting on an object are not causing it to accelerate and calculate to make 0 (all forces cancel out)
what is a free body diagram
a diagram where forces are drawn in their correct direction and represented by arrows
how do you add vectors
by drawing a diagram
what can you do to forces in the same direction when using F=ma
you can add or subtract them (F₁−F₂=ma)
what is drag
resistance in a fluid
what does it mean when an object is at terminal velocity
the forces are balances (resultant force =0)
what is the relationship between drag and velocity
drag is directly proportional to speed²
at terminal velocity what is the relationship between drag and weight
drag = weight = mg
resultant force equation (drag, weight)
resultant force = weight - drag
what does it mean when an object is at equilibrium
the resultant force = 0
if an object is in equilibrium what will the free body diagram look like
a triangle
