IB Syllabus focus: 'Equations for speed, linear velocity, angular velocity, acceleration, linear momentum, force and weight are in the SEHS data booklet. Calculations are limited to three terms for SL and four for HL.'
This subsubtopic focuses on recognizing the main equations in the SEHS data booklet, choosing the correct formula, using consistent units, and rearranging expressions accurately in short Newtonian sport calculations.
Using the SEHS data booklet
The SEHS data booklet gives you the core equations for speed, linear velocity, angular velocity, acceleration, linear momentum, force, and weight. In exams, success depends less on memorizing many formulas and more on identifying the correct quantity, selecting the matching equation, and substituting values with care. A common source of error is mixing scalar and vector quantities, especially when comparing speed with velocity.
Practice Questions
FAQ
Radians are the standard SI-based unit for angular measurement, so they fit naturally with physics equations.
Using radians also keeps rotational formulas mathematically consistent with other motion relationships. In higher-level mechanics, many equations only work directly when angle is measured in radians.
Degrees can still describe rotation clearly, but if a question expects SI units, convert to $rad\ s^{-1}$.a
A good method is:
write the full equation first
identify the quantity you need alone on one side
move terms one step at a time
substitute numbers only after rearranging
This reduces arithmetic mistakes and makes it easier for an examiner to award method marks.
If you substitute too early, the calculation often becomes harder to check.
Usually, the key issue is being reasonable and consistent.
A practical rule is to match the precision of the least precise value given in the question, unless your teacher or paper instructions say otherwise.
If your method is correct, a tiny rounding difference often does not lose the main marks. However, careless over-rounding during intermediate steps can produce a noticeably wrong final answer.
Use the value provided in the question whenever one is stated.
If no value is stated, follow the value normally accepted in your course materials or data booklet guidance. The difference between $9.8$ and $9.81$ is very small, but using the stated value shows accurate exam technique.
Do not switch values halfway through a calculation.
Physics notation is not completely universal. For example, one source may use $s$ for displacement, while another uses $x$.
In IB SEHS, what matters most is:
choosing the correct relationship
defining symbols clearly if needed
using consistent units
If the data booklet or question uses a particular symbol set, follow that version in the exam. Consistency is more important than the exact letter chosen.
