Why do cars have so many cylinders?

Why do cars have so many cylinders?
Cars have multiple cylinders to produce more power and reduce vibrations. The more cylinders in a car, the more explosions that are taking place, and the more power is produced. Multiple cylinders also contribute to smooth operation. Here's why:

The cylinder is filled with a piston, attached to a rod. The other end of the rod is attached to the crankshaft. As the piston moves up and down, so is the rod, which spins the crankshaft to create the circular drive motion. Now, as the crankshaft is spinning around, each cylinder is igniting to drive the piston and rod down to turn the shaft. Imagine if the engine only had one cylinder - the crankshaft would have to make a full revolution before it would receive another "push" from the rod. This produces very little power, and lots of vibration (your weedwacker is a single-cylinder engine. The next time you use it, feel how numb your hand becomes from the vibrations caused by a single cylinder). Compare that to a four, six, or even eight cylinder engine. Now one revolution of the crankshaft is receiving up to eight "pushes" to help it spin along its way. This smooths out the engine, balances the rotational forces and reduces vibration. Not to mention, eight explosions is a lot stronger than four, so you get more horsepower and torque.

Hope this answers your question.

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Jesse