Since I began teaching "Order of Magnitude" physics a few years ago, I collected many examples of physics estimates from daily life (and the daily life of physicists... which I admit does not necessarily reflect the population as a whole). Here are several examples. More should be added with time!

#### Solutions using scaling

These are solutions of problems that require scaling (i.e., comparing one the estimated "object" to other similar ones).

#### Solutions using simple dimensional analysis

These solutions require a relatively simple analysis since these problems have only one dimensionless numbers.

#### Elaborate Dimensional Analysis

In more general problems, there are several dimensionless numbers, which makes the analysis more complicated (but not much more!) and often utilizes Buckingham Pi Theorem.

#### Equipartition

Since different components in a system tend to equilibrate (e.g., the kinetic and potential energies of a system), equipartition is a useful tool in estimates.

#### Solutions requiring simple modeling

As a last resort, a problem's approximate solution can often be obtained through simple modeling.

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