Engines require fuel to undergo combustion, which generates the energy needed to power the machine. Petrol and diesel are commonly used fuels because they have high energy density and can be easily transported and stored.

Both living beings and machines require energy to perform work and sustain their operations. Energy is necessary for bodily functions in living beings, while machines need energy to operate their mechanical components and perform tasks efficiently. Without energy, neither living ...

Machines require a power source, such as electricity, fuel, or human effort, to perform their intended functions. They also often require maintenance and lubrication for optimal performance.

Examples of machines include cars, trucks, trains, airplanes, cranes, washing machines, and refrigerators, among others.

Animals may jump, run, fight, seek food, find shelter, or flee from predators. Some animals are also trained to perform tasks like lifting weights, carrying loads, or pulling carts.