Physics · Grades 6–12
Forces & equilibrium · Formula reference 1
Formula reference
Rule and assumptions
Perpendicular force resultant
Use this rule only for perpendicular components.
R = √(F₁² + F₂²)
Acceleration with opposing forces
Use consistent SI units and keep the stated direction convention.
a = (Fright − Fleft)/m
Weight in a given field
Mass is measured in kg; weight is a force measured in N.
Fᵍ = mg
Kinetic friction model
This is sliding friction with the stated coefficient, not a universal rule for static friction.
Fₖ = μₖN
Extension of an ideal spring
Stay in the linear elastic range; extension is not total spring length.
x = F/k
Further reading and review references
These are reference links, not copied exercises, institutional endorsement or proof of independent review.
Learning preview · independent educational and translation review required. Suggested grades are not official curriculum alignment.