In this post I am talking about the Safety Systems in cars.

INTRODUCTION:

             Improvements in roadway and automobile desings have reduced injury and death rates.This improvements could effect the simple cars mirrors or the complex braking system.
             
             What are Newton's three Laws of Motion

1. An object will maintain its motion unless acted on by an unbalanced force.
2. If an unbalanced force acts, an object will accelerate by 
3. For every force there is an equal and opposite force.

             What is impulse?

            Impulse is defined "as the integral of a force with respect no time",  the impact force. 

The size of the force depends on two factors:  

1. How much momentum the object had when moving. 

               2.  The time it takes for the object to stop.                                                                                                        

Stopping an object's momentum requires force acting over a period of time. When a car crashes, the force required to stop an object is very great because the car's momentum has changed instantly while the passengers' has not

TYPES OF SAFETY:

     

• Active Safety:

                    Is used to refer to technology assisting in the prevention of a crash.

• Passive Safety:

                    Is used to refer to components of the vehicle that help to protect occupants during a crash. The most common ones are the airbags, seatbelts and the  physical structure of the vehicle. 

                    They act trying to reduce the effect of an impact force. To get that, they increase the time the car takes to stop, it means, change its  momentum to cero in the most time as possible. 


In the next few lines I am explainig how some of this sistems work.


   SEAT BELTS

• How they work?

The idea of a seat belt is very simple: It keeps you from flying through the windscreen when your car comes to stop really fast or when you crash.  

This happen because of the car´s inertia or the impulse of the car.                      Inertia is an object's tendency to keep moving until something else works against this motion.

This is related to Newton's first law of motion.Things naturally want to keep going.

• Advantages & disadvantages of seat belts.

There are some advantages about seat belts, they can save your life in a collision or some other from accident, seat belts, in minor collisions, reduce the potential injury to drivers and passengers up to 50%.

Although they greatly reduce the incidence of death and serious injuries, seat belts are not perfect. Often, they contribute to accident-related injuries. In many cases, the fibres of the seat belt can cause harm to the chest and abdominal areas. this may include severe cuts and bruises where the seat belt lies across you, as well as more serious damage to the internal organs like tearing of the colon or diaphragm. In some cases the lumbar vertebrae may even be fractured or dislocated. Children are at the highest risk for seat-belt-related injuries.

   AIR BAGS

•  How Airbags Work?

The goal of an airbag is to slow the passenger's forward motion as evenly as possible in a fraction of a second.

•   Advantages & disadvantages of Airbags.

Air bags offer additional protection in car accidents, and when used in combination with seat belts, they reduce the risk of head, neck and chest injuries by 75 per cent. Inflation is automatically triggered by sudden impacts, providing immediate protection from striking the dashboard with your head in the case of a collision. Air bags deflate immediately after the collision so as not to suffocate the victim. 

Despite the obvious benefits, there also are some risks associated with air bags. Most prominently, the speed at which the air bag deploys can sometimes cause whiplash, potentially fatal head and chest injuries or concussions. This is especially true for drivers or passengers not wearing seat belts, as they may be thrown forward before the actual collision if the breaks are slammed on. 

ABS (Anti-lock Braking System)

• How ABS work?

ABS is an automobile safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up because the impulse of the car.

This is related to Newton's three laws of motion 

• Advantages & disadvantages of ABS.

An ABS generally offers improved vehicle control and decreases stopping distances on dry and slippery surfaces for many drivers; however, on loose surfaces like gravel or snow-covered pavement, an ABS can significantly increase braking distance, although still improving vehicle control.

          In conclusion, the how much secure are we in cars depends mostly of the driver rather than the safety features in our cars. If I would have to pick one of the safety devices,  I would pick Seat belts because they really can save your live in low speed crashes which are the most common.

This Post was made during my stance in Orroroo, South Australia in 2012.