Foundations in Mechanics & Biomechanics
Prof. Dr. Alessandro Del Vecchio · 7 concepts · 6 questions
Concept 1 / 7
Physical Quantities — Fundamental & Derived
Fundamental quantities (base units that cannot be expressed in terms of others):
| Quantity | Unit | Note |
|---|---|---|
| Length | m | |
| Mass | kg | 1 kg_mass → 9.81 N weight on Earth |
| Time | s | |
| Electrical charge | C | 1 C = 6.24×10¹⁸ electrons |
| Temperature | °C | 1/100 of the freezing–boiling range |
| Angle | degree / radian | 1 rad = 57°; full circle = 2π rad |
Derived quantities (combinations of fundamental units):
- Surface: m², Volume: m³
- Velocity (linear): m/s, Velocity (angular): deg/s or rad/s
- Acceleration (linear): m/s², Acceleration (angular): deg/s² or rad/s²
- Force [N = kg·m/s²]: Static force → equal-opposite static reaction; Dynamic force → inertial reaction = mass × acceleration
- Torque [Nm]: Static torque → equal-opposite static reaction torque; Dynamic torque → inertial reaction = moment of inertia × angular acceleration