<span>
The purpose of a gasoline car engine is to convert gasoline into motion
so that your car can move. Currently the easiest way to create motion
from gasoline is to burn the gasoline inside an engine.
Therefore, a car engine is an internal combustion engine -- combustion takes place internally.
There is such a thing as an external combustion engine. A steam engine
in old-fashioned trains and steam boats is the best example of an
external combustion engine. The fuel (coal, wood, oil, whatever) in a
steam engine burns outside the engine to create steam, and the steam
creates motion inside the engine. Internal combustion is a lot more
efficient (takes less fuel per mile) than external combustion, plus an
internal combustion engine is a lot smaller than an equivalent external
combustion engine. This explains why we don't see any cars using steam
engines.
To understand the basic idea behind how a reciprocating internal
combustion engine works, it is helpful to have a good mental image of
how "internal combustion" works.
One good example is an old Revolutionary War cannon. You have probably
seen these in movies, where the soldiers load the cannon with gun powder
and a cannon ball and light it. That is internal combustion, but it is
hard to imagine that having anything to do with engines.
A potato cannon uses the basic principle behind any reciprocating
internal combustion engine: If you put a tiny amount of high-energy fuel
(like gasoline) in a small, enclosed space and ignite it, an incredible
amount of energy is released in the form of expanding gas. You can use
that energy to propel a potato 500 feet. In this case, the energy is
translated into potato motion. You can also use it for more interesting
purposes. For example, if you can create a cycle that allows you to set
off explosions like this hundreds of times per minute, and if you can
harness that energy in a useful way, what you have is the core of a car
engine! </span>
shhhh hahahaha ahhhhhhhh ahhhh
the upward force the desk pushes on the book.
from the free body diagram of the book, it is clear that on the book, there are two forces acting.
1) normal force F by the desk in Upward direction.
2) force of gravity by earth in downward direction.
The Upward normal force by the desk on the book balances the force of gravity by earth in downward direction. that is why the book remains stationary on the desk.
Considering that while traveling on a road with a<u> final speed of 15 m/s</u>, and an<u> initial speed of 24 m/s</u>, with a given time <u>of 12 seconds.</u>
To calculate the acceleration, we apply the following formula:
α = Vf - Vo/t
We add our data into the formula and solve:
α = 15 m/s - 24 m/s/12 sec
α = -0.75 m/s²
Therefore, the acceleration of the car is -0.75 m/s².
<h2>Skandar</h2>
