reduce smoke Mercedes Public benefits - using a car
In countries deprived from wide door-to-door public transport and with low density, such as Australia, the automobile plays an important role on the mobility of citizens. Public transport, by comparison, becomes increasingly uneconomic with lower population densities. Hence cars tend to dominate in rural and suburban environments with public economic gains.
The automobile industry, mainly in the beginning of the 20th century when the high motorization rates were not an issue, had also an important public role, which was the creation of jobs. In 1907, 45,000 cars were produced in The United States, but 28 years later in 1935 3,971,000 were produced, nearly 100 times as many. This increase in production required a large, new work force. In 1913 13,623 people worked at Ford Motor Company, but by 1915 18,028 people worked there.10 Bradford DeLong, author of The Roaring Twenties, tells us that, "Many more lined up outside the Ford factory for chances to work at what appeared to them to be (and, for those who did not mind the pace of the assembly line much, was) an incredible boondoggle of a job.10" There was a surge in the need for workers at big, new high-technology companies such as Ford. Employment largely increased.
Źródło: https://en.wikipedia.org/wiki/Economics_of_car_use
Big end bearings
Lubrication
Diagram of an engine using pressurized lubrication
Wikimedia Commons has media related to Internal combustion piston engine lubrication systems.
Surfaces in contact and relative motion to other surfaces require lubrication to reduce wear, noise and increase efficiency by reducing the power wasting in overcoming friction, or to make the mechanism work at all. At the very least, an engine requires lubrication in the following parts:
Between pistons and cylinders
Small bearings
Big end bearings
Main bearings
Valve gear (The following elements may not be present):
Tappets
Rocker arms
Pushrods
Timing chain or gears. Toothed belts do not require lubrication.
Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
About cars - safety
Road traffic accidents are the largest cause of injury-related deaths worldwide.6 Mary Ward became one of the first documented car fatalities in 1869 in Parsonstown, Ireland,43 and Henry Bliss one of the United States' first pedestrian car casualties in 1899 in New York City.44 There are now standard tests for safety in new cars, such as the EuroNCAP and the US NCAP tests,45 and insurance-industry-backed tests by the Insurance Institute for Highway Safety (IIHS).46
Worldwide, road traffic is becoming ever safer, in part due to efforts by the government to implement safety features in cars (e.g., seat belts, air bags, etc.), reduce unsafe driving practices (e.g., speeding, drinking and driving and texting and driving) and make road design more safe by adding features such as speed bumps, which reduce vehicle speed, and roundabouts, which reduce the likelihood of a head-on-collision (as compared with an intersection).
Źródło: https://en.wikipedia.org/wiki/Automobile_safety