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Work - kinetic energy principle . Darkhan Kyzaibayev Yernar Beketov. Work-Energy Principle. The change in the kinetic energy of an object is equal to the net work done on the object.
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Work - kinetic energy principle DarkhanKyzaibayev YernarBeketov
Work-Energy Principle The change in the kinetic energy of an object is equal to the net work done on the object.
This fact is referred to as the Work-Energy Principle and is often a very useful tool in mechanics problem solving. It is derivable from conservation of energy and the application of the relationships for work and energy, so it is not independent of the conservation laws. It is in fact a specific application of conservation of energy. However, there are so many mechanical problems which are solved efficiently by applying this principle that it merits separate attention as a working principle. • For a straight-line collision, the net work done is equal to the average force of impact times the distance traveled during the impact.Average impact force x distance traveled = change in kinetic energy • If a moving object is stopped by a collision, extending the stopping distance will reduce the average impact force.
We studied about work-energy principles in the class in 8th week. Given that, knowing these principles are very important for everyone, the lecture about work-energy principles was very compelling for us. Particularly, we were interested in the usage of work – kinetic energy principle in everyday life. Therefore, we came up with the idea to study about this principle further in details ; consequently, desire to know more about this principle inspired us to make this project.
No Seatbelt! • With no seatbelt to stop the driver with the car, the driver flies free until stopped suddenly by impact on the steering column, windshield, etc. The stopping distance is estimated to be about one • fifth of that with a seatbelt, causing the average impact force to be about five times as great. The work done to stop the driver is equal to the average impact force on the driver times the distance traveled in stopping. A crash which stops the car and driver must take away all its kinetic energy, and the work-energy principle then dictates that a shorter stopping distance increases the impact force.
New insight • The work and energy principles are crucial in our daily live. Most people don’t even realize how these principles are related to each other. This relation is well illustrated in the example of the usage of the seatbelt. The seatbelt is very useful in the way of saving our lives. It stops a person while a crash stops a car’s kinetic energy then work and energy principle occurs. Therefore, the person who doesn’t use a seatbelt puts in danger not only his/her lives but other passengers’ lives respectively. This is a great lesson for everyone to take more responsibility and to study physics.