If maths is what breaks your Physics answers, repair that one step and go back. The aim is to fix the gap, not to restart the syllabus.
This page is for students whose Physics understanding is sound but whose working fails on algebra, units or powers of ten. It is one of the help pages for SPM Physics.
What does this sound like?
A student might say, “I understand the concept, but I lose the marks when I rearrange.” Or, “I get the physics right and the answer comes out a thousand times too big.”
These are maths gaps. They are small, and they are fixable without touching the rest of the course.
What usually causes it?
Three academic causes are common.
- A skill from earlier years, such as rearranging a formula with fractions, was never fully secure.
- Powers of ten and unit conversions were learnt as rules, without feeling for size.
- Physics practice covers many skills at once, so one weak skill hides among the rest.
A worked example
Take the equation v² = u² + 2as. A student needs a when v = 20 m s⁻¹, u = 4 m s⁻¹ and s = 48 m.
Rearranging. Subtract u² from both sides: v² − u² = 2as. Divide by 2s: a = (v² − u²) ÷ 2s. A common slip is to write a = v² − u² ÷ 2s, which divides only one term.
Substituting. a = (400 − 16) ÷ 96 = 384 ÷ 96 = 4 m s⁻².
Powers of ten. A second problem gives a wavelength of 650 nm. In metres, 650 × 10⁻⁹ = 6.5 × 10⁻⁷ m. If the student writes 6.5 × 10⁻⁵, the answer is off by a factor of 100.
Each slip is one line. Repair the rearranging skill and the powers-of-ten skill, and the Physics works.
What can you do on your own?
Follow a short routine.
- Take three recent wrong answers and mark the first incorrect line in each.
- Name the skill, such as “rearranging” or “converting nm to m”.
- Practise that skill alone for a few short sessions, then return to a Physics question.
The foundations section has lessons for each: rearranging a formula with fractions, calculating with scientific notation, and calculating a straight line gradient. The prerequisite gap finder can help you name the skill.
When might one-to-one tuition help?
Naming the failing skill is the hard part, because your own working is hard to see from outside. If you cannot tell whether a wrong line is a Physics error or a maths error, it may be worth having a second pair of eyes.
A one-to-one teacher can read your working, name the step, and set a repair task that takes only a session or two. The repair can then be tied back to the Physics topic you were studying. See online one-to-one Physics tuition or the one-hour trial class (from RM50).
What to read next
Start with the skill you named. For most students that is rearranging a formula with fractions.