1. Read the problem carefully , without missing a seemingly minor reservations.Note that in most cases the problem is the author of a good expert in their field, and that means that the full-significant phrases in a problem there.

2. Write down all the data from the units. data explicitly you see in the form of numbers, but do not forget that often the problem found and hidden data in the form of phrases such as "will start from the scene" (means starts to move without initial velocity, that is, writing that the initial velocity is zero) "has been dropped from a height of ..." (if not stated otherwise, we can suspect that this movement was also no initial speed), and so on.

Switch all in SI (system which is bu

ilt on the basic units meter-kilogram-second).Remember that the physical quantities into other physical quantities can not be translated!For example, liters can be converted into cubic meters (ie, the amount can be transferred from one unit to another volume), but the translation liters per kilogram (of unit volume per unit mass) is like chess pieces that translate into humans.

3. Think about what theory to describe the situation of the problem is best suited (depends on the data of physical quantities).
example: a body falling from a height of a school course of physics can be described by equations of the kinematics of uniformly accelerated motion, but you can with the help of the law of conservation of energy or Newton's second law.In the case of complex or combined task will need most of the formulas (laws).

Try chosen formula.If there are too many unknowns in the equation, there are only three options:
well.You have chosen the wrong path, that is a simple task, but it is necessary to apply other laws (or search for hidden data),
b.the task is more complicated than originally seemed, append the laws that describe the situation of the other sections and decide everything as a system of equations,
in.the originator of the problem was wrong and the problem is not formulated exactly or gave no data.

4. Once you get an equation or system of equations, solve it, get an answer and think - from the point of view of common sense answer may turn out that way?
For example, if you want to speed the tram, it can not be 1,000,000,000 km / sec (does not happen in our world such).Also check out the response of units (in the calculations do not forget the laws of mathematics to transform not only the numerical expressions, but their units).