Final answer:
In a four-stroke internal combustion engine, a 7-inch connecting rod is attached to the piston and the crankshaft. It does not connect directly to the camshaft or the flywheel. The flywheel helps smooth out engine vibrations, and unused energy in the engine is typically converted into heat.
Step-by-step explanation:
In the context of a four-stroke internal combustion engine, a 7-inch connecting rod is typically fastened to the piston at one end and to the crankshaft at the other. This allows the up-and-down motion of the piston to be converted into the rotational motion that powers the vehicle. The connecting rod does not attach directly to the camshaft or the flywheel.
During the intake stroke, air and fuel are mixed as the piston moves downwards, pulling the mixture into the cylinder. In the compression stroke, this mixture is compressed by the rising piston. When the air-fuel mixture is ignited in the power stroke, the resulting expansion forces the piston down, and during the exhaust stroke, waste gases are expelled. The crankshaft rotates throughout these cycles, converting the piston's linear motion into rotational motion, which ultimately drives the vehicle's wheels.
The flywheel's role is to smooth out engine vibrations by acting as a counterweight, keeping the engine running smoothly through the inertia and momentum it provides amidst the thrust of individual piston firings. Lastly, unused energy in an engine, not harnessed for work, is often converted into heat due to inefficiencies.