UTS ENGINEERING
68037
Physical Modelling
Mechanics, Statics, Dynamics & Energy Systems
Bachelor of Engineering (Honours) | Year 1
University of Technology Sydney
, Topic 1: Units, Dimensions & Estimation
1.1 SI Units
All physical quantities are expressed in SI (Système International) units. The seven base units are:
• Length: metre (m)
• Mass: kilogram (kg)
• Time: second (s)
• Current: ampere (A)
• Temperature: kelvin (K)
• Amount: mole (mol)
• Luminous intensity: candela (cd)
Derived Units
Force: Newton (N) = kg·m/s²
Energy: Joule (J) = N·m = kg·m²/s²
Power: Watt (W) = J/s = kg·m²/s³
Pressure: Pascal (Pa) = N/m² = kg/(m·s²)
⚡ Exam Tip: Always check dimensional consistency. Both sides of any equation must have the same
units.
Topic 2: Kinematics — Motion in 1D & 2D
2.1 Key Definitions
Displacement: s — change in position (vector, metres)
Velocity: v = ds/dt (vector, m/s)
Speed: |v| — magnitude of velocity (scalar)
Acceleration: a = dv/dt = d²s/dt² (vector, m/s²)
2.2 SUVAT Equations (Constant Acceleration Only)
These equations apply only when acceleration is constant:
v = u + at
s = ut + ½at²
v² = u² + 2as
s = ½(u + v)t
where: s = displacement, u = initial velocity, v = final velocity, a = acceleration, t = time
⚡ Exam Tip: Identify the 3 known variables and 1 unknown. Pick the SUVAT equation that contains
exactly those 4 variables.
68037
Physical Modelling
Mechanics, Statics, Dynamics & Energy Systems
Bachelor of Engineering (Honours) | Year 1
University of Technology Sydney
, Topic 1: Units, Dimensions & Estimation
1.1 SI Units
All physical quantities are expressed in SI (Système International) units. The seven base units are:
• Length: metre (m)
• Mass: kilogram (kg)
• Time: second (s)
• Current: ampere (A)
• Temperature: kelvin (K)
• Amount: mole (mol)
• Luminous intensity: candela (cd)
Derived Units
Force: Newton (N) = kg·m/s²
Energy: Joule (J) = N·m = kg·m²/s²
Power: Watt (W) = J/s = kg·m²/s³
Pressure: Pascal (Pa) = N/m² = kg/(m·s²)
⚡ Exam Tip: Always check dimensional consistency. Both sides of any equation must have the same
units.
Topic 2: Kinematics — Motion in 1D & 2D
2.1 Key Definitions
Displacement: s — change in position (vector, metres)
Velocity: v = ds/dt (vector, m/s)
Speed: |v| — magnitude of velocity (scalar)
Acceleration: a = dv/dt = d²s/dt² (vector, m/s²)
2.2 SUVAT Equations (Constant Acceleration Only)
These equations apply only when acceleration is constant:
v = u + at
s = ut + ½at²
v² = u² + 2as
s = ½(u + v)t
where: s = displacement, u = initial velocity, v = final velocity, a = acceleration, t = time
⚡ Exam Tip: Identify the 3 known variables and 1 unknown. Pick the SUVAT equation that contains
exactly those 4 variables.
