- 2067 Asoj · 3 marks
Compare static equilibrium and equilibrium
Short answer
Equilibrium means resultant force and moment are zero, so acceleration is zero; velocity may be zero or constant. Static equilibrium is the special case where the body is also at rest, so velocity is zero. Every static equilibrium is equilibrium, but not vice versa.
Compare between the static equilibrium and equilibrium.
Equilibrium is the condition in which the resultant force and resultant moment on a body are zero (ΣF = 0, ΣM = 0), so the body has no acceleration. The body may be at rest or moving with constant velocity.
Static equilibrium is the special case in which the body is also at rest, so its velocity is zero as well as its acceleration.
| Point | Static equilibrium | Equilibrium (general) |
|---|---|---|
| Velocity | Zero, body at rest | Zero or constant |
| Net force and moment | Zero | Zero |
| Acceleration | Zero | Zero |
| Studied in | Statics | Statics and dynamics (uniform motion) |
| Example | A beam carrying a load, a bridge | A car moving at constant speed on a straight road; a body at rest |
Every static equilibrium is an equilibrium, but not every equilibrium is static. The same equations ΣF = 0 and ΣM = 0 are used for both.
✓ Answer checked by Claude Opus 5.5 (high effort)
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