# School:Physics and Astronomy/Style

This page will be a handbook of style for writing physics text for the School of Physics and Astronomy. If you're looking for the general manual of style, see the Wikiversity:Manual of Style.

## Language

Either U.S. or UK English should be used consistently within any individual learning resource. Try to make sentences clear and concise; we want these resources to be easy to grasp.

The first time an important word is used, it should be bolded and defined. It wouldn't be a bad idea to link significant terms to Wikipedia the first time (atom, electron, Schrodinger's equation, etc.).

## Mathematics

Mathematical expressions should be presented in LaTeX format for anything of significant complexity. A good rule of thumb is that, if you would have to use parentheses in the expression, you should put it in LaTeX.

For example, F = m*a and F = dp/dt are fine in plaintext, but

${\displaystyle \Delta p=\int _{t_{i}}^{t_{f}}F(t)\,dt}$

needs to be in TeX.

As seen above, an equation that breaks the flow of text (that is, changes line spacing) should be put on a separate line. Equations that will be referred to should be numbered:

Gauss' law
(1) ${\displaystyle {\vec {\nabla }}\cdot {\vec {E}}\equiv {\frac {\rho }{\epsilon _{0}}}}$
(2) ${\displaystyle \oint _{S}{\vec {E}}\cdot d{\vec {a}}\equiv {\frac {Q_{total}}{\epsilon _{0}}}}$

## Units

Units should always be expressed in the system of units most widely used in that subject, which is usually SI. In exceptional cases, such as optical astronomy, the relation of the units to the SI system or method of calibration must be given. When a new unit is introduced, it is acceptable (and probably desirable) to give conversion factors for other units; conversion into the fundamental SI units should always be given:

The meter is the SI unit of distance and is abbreviated 'm'. 1 meter = 1 m = 3.28 feet
The volt is the SI unit of electrical potential and is abbreviated 'V'.
${\displaystyle 1\mathrm {V} =1{\mbox{volt}}=1{\frac {\mathrm {J} }{\mathrm {C} }}=1{\frac {\mathrm {N} \,\mathrm {m} }{\mathrm {A} \,\mathrm {s} }}}$

Units are treated like ordinary nouns.