Forces and motion Flashcards
What is friction
Friction is a force that is created when two objects/surfaces rub together
Newtons first law
An object at rest will remain at rest unless acted on by an unbalanced force
Newtons second law
force equals mass times acceleration
Newtons third law
For every action, there is an equal and opposite reaction
What is drag
a drag is a force acting opposite to the relative motion
what is gravity
the force that attracts a body towards the center of the earth, or towards any other physical body having mass.
when is friction good and when is friction bad
good- to keep your car on the road, when walking, when playing rugby
bad- ice skating, the motor in your car, and when moving something produces heat
how do you calculate for speed
speed equals distance over time
how do you calculate for distance
distance equals speed times time
how do you calculate for time
time equals distance over speed
how do you find an average
add up all the data and divide by however many you added
what is mass
how much stuff something has
how is mass measured
in kgs
can mass change
no, mass remains constant
what is weight
weight is the force of gravity on a mass
how is weight measured
in newtons (N)
can weight change
yes, weight changes depending on gravity
how do you calculate weight/force
force equals mass times acceleration
gravity on earth is measured at what
10ms-1
a newton is how much
one newton is 10 kgs
what is a pivot
fixed point around where the lever turns
what is an effort
where applied by you
what is a load
force you want to apply a force too
what is the order of a 1st class lever
e,p,l or l,p,e
what is the order of a 2nd class lever
p,l,e or e,l,p
what is the order of a 3rd class lever
p,e,l or l,e,p
