Question

The first law of thermodynamics states that energy can't be created or destroyed. If people can't create energy, where do we get energy to do work?
Options: the Sun and moon, food and fossil fuels, our heart and mind, Earth's orbital momentum

Answer 1

Correct answer: B). Food and fossil fuels

The energy can not be created nor destroyed but it can be transformed into another form. The ultimate source of energy on this planet is the sun, the sun provides sunlight where sunlight is converted into chemical energy, which is used by plants to prepare food. Then we consume food prepared by plants to get energy and perform various types of work like movement, reproduction, growth etc. In this, the chemical energy is converted into mechanical energy.