1.2.4 CAR SAFETY

HideShow resource information
What is thinking distance?
The distance travelled by the car from when the driver sees the problem and the brakes are applied (reaction time)
1 of 15
How do you calculate thinking distance?
vehicle speed x reaction time
2 of 15
What is breaking distance?
distance travelled by a vehicle from the moment when the breaks are applied until the vehicle comes to a stop
3 of 15
What is stopping distance?
sum of thinking and breaking distances
4 of 15
Describe the factors that affect thinking distance
alcohol levels // tiredness // distractions // age - reaction time decreases with age
5 of 15
Describe the factors that affect breaking distance
road surface (wet, icy, oily) // quality of breaks // quality of tyres (all these factors decrease amount of friction)
6 of 15
Describe the factors that overall impact upon the stopping distance
speed, mass, gradient of road (uphill means shorter distance) // greater speed means greater distance // greater mass means greater distance
7 of 15
What do air bags and seat belts do?
Reference to K.E.=Fs or 1⁄2 mv2=Fs // prevents collisions with steering wheel/ windscreen/dashboard // time / distance for stopping is more // smaller deceleration
8 of 15
What is a crumple zone?
part of a car which has been specifically designed to squash up or crumple easily in the event of a crash // absorbs energy // directs engine away from passengers
9 of 15
What happens when a car decelerates quickly?
objects within the car obey Newton's 1st law // continue to move forwards at car's impact velocity until a force changes their motion
10 of 15
How do air bags work?
tiny accelerometer detects large deceleration // accelerometer consists of two rows interlocking teeth // on deceleration teeth collide generating a voltage // magnetic sensor triggers electrical signal to release bag
11 of 15
How do GPS work?
several satellites used / satellite in high orbit transmit radio / micro waves // transmission contains identity, transmission time, position //delay time is determined and is used to calc distance between - multiple transmissions (trilateration)
12 of 15
What are GPS used for?
navigation for boats/ cars/ planes // vehicle tracking // mobile phones locations
13 of 15
Describe car safety in terms of F=ma
change in v = acceleration // big a = small t = big F // big t = small a = small F // increase in impact time decreases resultant force
14 of 15
Describe car safety in terms of W=Fx
on impact energy is transferred // KE goes into sound or thermal // work is done transferring this energy // work done = KE lost // maximise x will minimise F
15 of 15

Other cards in this set

Card 2

Front

How do you calculate thinking distance?

Back

vehicle speed x reaction time

Card 3

Front

What is breaking distance?

Back

Preview of the front of card 3

Card 4

Front

What is stopping distance?

Back

Preview of the front of card 4

Card 5

Front

Describe the factors that affect thinking distance

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Forces resources »