Rotation 1 Physics

displacement formula

Δs = sf - si

speed formula

v=s/t

velocity formula

v=s/t with direction

acceleration formula

a = final velocity - initial velocity / time

distance definition

how far an object travels

displacement definition

the difference between an objects final position and its initial position via a straight line

scalar definition

magnitude

vector definition

magnitude and direction

speed definition

the rate of change of distance

velocity definition

the rate of change of displacement

instantaneous speed definition

speed at any one moment

acceleration definition

the ra at which velocity changes

thinking distance definition

distance travelled whilst thinking about braking

braking distance definition

the distance it takes for the car to slow down and stop

newtons 1st law definition

an object at rest remains at rest, and an object in motion will travel at the same speed and direction until an unbalanced force acts upon it

newtons 2nd law

f=ma

newtons 3rd law definition

for every action there is an equal but opposite reaction

Inertia definition

the tendency of an object to remain in its state of rest or uniform motion

factors that affect braking distance

* tires⬇=distance↑
* weather↑=distance↑
* worn brakes = distance↑
* surface of road

factors that affect thinking distance

* age↑ = distance↑
* coffee = distance↑
* distraction = distance↑
* visibility⬇ = distance↑
* sleep⬇ = distance↑
* alcohol/drugs = distance↑

factors that affect stopping and thinking distance

speed. stopping distance and thinking distance increase with speed.

units for acceleration

ms-2

units for force

N

units for mass

kg

car safety features act to…

prevent a collision and/or reduce the force during a collision

what law works to prevent collisions

1st

what law works to reduce the force

2nd

how does newtons 2nd law reduce the force of a collision

safety features rely on newtons second law by increasing collision time, which reduces acceleration, therefore reducing force

2nd law safety features

1st law safety features

* rakes
* speed limits
* seat belts
* cargo barriers
* head rests

2nd law safety features

* crumple zones
* airbags
* collapsing steering columns