The goal of any science is to gain knowledge about different spheres of human existence. One of these spheres is the world around us, nature, the universe. They are studied by the science of physics. Let’s talk briefly about what phenomena physics studies, what is included in the sphere of interest of this science.

Physical phenomena.
What does physics study? To answer this question, it is necessary to say that the very name of the science “physics” comes from the ancient Greek word “φύσις” (“fusis”), nature. Nature is all that surrounds us. Air, water, objects, living things, the Earth, the sun, the cosmos, the universe – all this is nature. Nature is eternal and infinite.

Mechanical phenomena are phenomena resulting from motion (narrowly defined as movement in space) and the interaction of objects. This also includes the phenomenon of mutual attraction of celestial bodies. Light phenomena are everything associated with the propagation and action of light. Thermal phenomena include the production of heat, and the exchange of heat between bodies. Electrical phenomena are phenomena related to such special properties of matter as electric charges and magnetism.

Physical laws
Observations and experiments show that the vast majority of phenomena are not chaotic, but quite predictable and regular. For each phenomenon, a cause, a consequence, and a series of interrelated phenomena can be specified.
For example, any object on Earth tends to fall to its surface. Falling, it acquires a certain velocity. If it touches other objects, it loses some of its speed, and the objects it touches begin to move. These are all mechanical phenomena studied in physics.

For each specific object, you can specify the measure with which the fall will occur, followed by the touching of other objects and subsequent movements. All these measures – the degree of interaction between the Earth and the object, the velocity of the object falling and its change over time, the interaction of the object with others, and the rates of subsequent movements – are called physical quantities. Physical quantities are related to each other by mathematical formulas and laws, which are called physical laws.

For example, the basic law of dynamics (Newton’s second law) relates such quantities as the force acting on the body, the mass of the body and the acceleration obtained by the body.

Knowing the force acting on the body and its mass, we can find the acceleration the body receives as a result of that force. For our example, knowing the force of gravity acting on an object and its mass, we can find the acceleration produced by that object. And then, knowing acceleration and time, using the laws of kinematics (a special branch of physics), we can find the speed of the falling object at any point in time.

The goal of physics is to discover and study the physical laws that operate in nature and to use them in life. In any field studied by physics, there are a number of physical laws that describe phenomena in their most general form. The simultaneous action of all these laws gives rise to the diversity of nature that exists in the world.