Prepared by Richard Fowler for the Institution of Fire Engineers (IFE) to assist students in Fire Engineering Science papers.
Designed to complement other learning, consolidating essential formulas for student’s understanding and applications.
Section 1: L3 Diploma – Fire Engineering Science
Equations of Linear Motion
Newton’s Laws of Motion
Mass, Weight, and Momentum
Work, Energy, and Power
Hydraulics
Mathematics
Equilibrium in Mechanical Systems
Electricity
Heat
The Gas Laws
Transformer Ratios
Section 2: L4 Certificate – Fire Engineering Science
Hydraulics
Liquid Flow in Open Channels
Measuring Flow through an Open Channel
Electricity
Fire Dynamics (Law’s Law)
Recommended Calculator
Key Equations:
v = u + at
s = (u + v)/2 * t
s = ut + 1/2 at^2
s = v t - 1/2 at^2
v^2 = u^2 + 2as
Variables:
v = Final velocity (m/s)
u = Initial velocity (m/s)
a = Acceleration (m/s²)
t = Time (s)
s = Distance (m)
First Law: An object remains at rest or in uniform motion unless acted upon by an external force.
Second Law: Acceleration is proportional to the net force acting on it (F = ma
).
Third Law: For every action, there is an equal and opposite reaction.
Force Equation: F = m x a
F = Force (N)
m = Mass (kg)
a = Acceleration (m/s²)
Momentum Equation: p = mv
p = Momentum (kg·m/s)
Power Equation: P = W/t
W = Work done (J)
P = Power (W)
Kinetic Energy Equation: KE = 1/2 mv^2
Potential Energy Equation: PE = mgH
Pressure Equation: P = ρgH
Flow Rate through Nozzle: L = 2/3d²√P
Area of Circle: A = πr²
Volume of Cylinder: V = πr²h
Volume of Sphere: V = 4/3πr³
Conditions of Equilibrium:
For straight motion, net force = 0.
For rotation, net moment = 0.
Ohm's Law: V = IR
Power Calculation: P = IV
Heat Change Equation: c = ∆Q/∆T
Specific Heat Capacity: C = ∆Q/m × ∆t
Boyle’s Law: P1V1 = P2V2
Charles’s Law: V1/T1 = V2/T2
Ideal Gas Law: PV = nRT
Transformer Equation: VP/VS = NP/NS = IS/IP
Bernoulli’s Equation: P1 + ρgH1 + 1/2 ρv1² = P2 + ρgH2 + 1/2 ρv2²
Flow Rate Equation: Q = v × A
Rectangular Weir Flow Equation: Q = 2/3 × C × L × (2g × H)^{1/2}
Inductive and Capacitive Reactance: XL = 2πfL
(Inductor), XC = 1/(2πfC)
(Capacitor)
Law’s Law:
tf = k × L / (Aw × At)^{1/2}
Where tf = fire resistance time (min).
Recommended Model: Casio fx-85GT Plus or fx-85GTX
Key Functions to Practice: Fractions, result toggling, memory clearing.