Tips for schoolchildren: how to solve problems in physics?

Any problem in physics, even non-standard, olympiad, is solved very simply, if you think carefully. True, you must not forget a few subtleties …

Attention, this algorithm is developed on the basis of own experience of studying at school, university and work as a physics teacher, and is not universal!

1. Read the task carefully, without missing seemingly insignificant reservations. Note that in most cases, the author of the task is a good specialist in his field, which means that there are no completely insignificant phrases in the task.

2. Write down all data with units. You see the data in explicit form in the form of numbers, but do not forget that often the hidden data in the form of phrases like “starts from a place” is also contained in the task (that means, it starts moving without an initial speed, that is, we write that the initial speed is zero), "dropped from a height …" (unless otherwise stated, then we can suspect that this movement was also without initial speed) and so on.

Translate everything into the SI system (a system that is built on the basic units of measure kilogram-meter-second). Remember that physical quantities cannot be converted to other physical quantities! For example, liters can be converted into cubic meters (that is, the volume can be converted from one volume unit to another), but converting liters to kilograms (from volume units to mass units) is the same as translating chess pieces into people.

3. Think about which theory to describe the situation from the problem is most suitable (depends on the data of physical quantities).

For example: a fall of a body from a height in a school physics course can be described by the kinematics formulas of uniformly accelerated motion, or it can also be done using the energy conservation law or Newton’s second law. In the case of a complex or combined task, most of the formulas (laws) will be needed.

Try applying the selected formulas. If there are too many unknowns in the equation, only three options are possible:

a. you chose the wrong path, that is, the task is simple, but you need to apply other laws (or look for hidden data), b. the task is more complicated than it seemed initially, write down the laws that describe the situation from other sections and solve everything as a system of equations, in. the compiler of the problem was mistaken and did not formulate the problem accurately or did not give all the data.

4. After you get an equation or a system of equations, solve it, get an answer, and think - from the point of view of common sense, the answer can be just that?

For example, if you calculate the speed of a tram, then it cannot be 1, 000, 000, 000 km / s (this does not happen in our world). Also check the answer according to units of measurement (when calculating, do not forget to convert not only numerical expressions, but also their units of measurement according to the laws of mathematics).