A four cycle engine works with 4 basic steps to a successful rotation of the crankshaft: the intake, compression, power and exhaust stroke. Each engine cylinder has four openings for the intake, exhaust, spark plug and fuel injection. ... The compression makes the air-fuel combination volatile for easier ignition.
It’s positive when you use energy for work
Answer:
light travels as a wave. but unlike sound waves or water waves, it doesn't need any matter or material to carry it's energy along