forces in balance Flashcards
what is a vector quantity?
a vector quantity has a magnitude. size and direction.
what is a scalar quantity
a scalar quantity has a magnitude size but no direction.
what are some examples of vector quantities? (3)
force.
velocity.
momentum.
what are some examples of scalar quantities?
speed.
distance.
mass.
how are vectors represented?
with an arrow thats size and direction represent magnitude and direction.
what is a force?
a push or pull on an object caused by an interaction with something.
what are the 2 types of forces?
contact.
non contact.
what is a contact force?
a force that acts when 2 objects are touching. such as friction or air resistance
what is a non contact force?
a force that acts when objects are not touching. such as gravity or magnetic forces
what is an interaction pair?
a pair of forces that are equal and opposite. on 2 interacting objects
what is gravitational force?
a force of attraction between masses. gives things weight
what is mass?
the amount of matter in an object.
what is weight?
the force acting on an object due to gravity.
what is the formula for weight?
weight newtons = mass kg x gravitational field strength N/kg
what does a free body diagram show?
all the force acting on an object or system. arrows represent the size of a force
what is a resultant force?
the overall force on an object.
what happens when a force moves an object?
work is done. mechanically
what is the formula for work done using force?
work done jules = force newtons x distance m
what is a scale drawing used for?
it helps you work out the resultant force.
how do you draw a scale drawing?
- draw a scale drawing of the forces acting 1cm = 1N for example
- join the 2 point of the forces looks like a triangle
- measure the length of the joining line for the force and measure the angle. for a bearing
what does it mean if an object is in equilibrium?
its forces are balanced. resultant force is 0
what does it mean to resolve a force?
split the force into horizontal and vertical components. up/down left/right
what can happen if you apply more than one force to an object? one is bending
- bending.
- stretching.
- compression.
what is an elastic object?
an object that can be elastically deformed. returns to its original shape and length
what does inelastically deformed mean?
an object doesn’t return to its original shape and length.
what is the formula for force using extension?
force newtons = spring constant N/m x extension m
what is a moment?
the turning effect of a force.
what is the formula for a moment?
moment Nm = force newtons x distance of force from pivot m
what are 2 force multipliers?
lever.
gear.
