A Car Engine Supplies 2.0×10 3 Joules of Energy

Introduction

A car engine is a complex machine that converts the chemical energy of gasoline into mechanical energy. This mechanical energy is then used to power the car’s wheels. In order to understand how a car engine works, it is important to first understand the concept of energy.

Energy

Energy is a scalar quantity that describes the ability of a system to do work. In other words, energy is the capacity to cause change. There are many different forms of energy, including kinetic energy, potential energy, thermal energy, and chemical energy.

Kinetic energy is the energy of motion. An object has kinetic energy if it is moving. The kinetic energy of an object is equal to one-half of its mass times its velocity squared.

$$KE = 1/2 mv^2$$

Potential energy is the energy of position. An object has potential energy if it is located in a force field. The potential energy of an object is equal to its mass times its acceleration due to gravity times its height.

$$PE = mgh$$

Thermal energy is the energy of heat. An object has thermal energy if it has a temperature. The thermal energy of an object is equal to its mass times its specific heat capacity times its temperature.

$$Q = mcDelta T$$

Chemical energy is the energy stored in the bonds between atoms. An object has chemical energy if it is composed of atoms that are bonded together. The chemical energy of an object is equal to the energy required to break the bonds between its atoms.

$$E = Nhnu$$

Car Engines

A car engine is a type of heat engine. A heat engine is a device that converts thermal energy into mechanical energy. Car engines work by burning gasoline in a combustion chamber. The combustion of gasoline produces heat, which is then used to expand a gas. The expanding gas pushes on a piston, which in turn causes the crankshaft to rotate. The rotating crankshaft powers the car’s wheels.

The efficiency of a car engine is the ratio of the mechanical energy output to the thermal energy input. The efficiency of a car engine is typically around 25%. This means that for every 100 joules of thermal energy that is input into the engine, only 25 joules of mechanical energy is output.

Conclusion

Car engines are complex machines that convert the chemical energy of gasoline into mechanical energy. The efficiency of a car engine is around 25%.