1.
external force; outside force
A force applied to an object or system from outside, as opposed to forces generated internally. Used in physics, engineering, and figuratively for outside pressure or influence.
外力が加わると変形する。
It deforms when external force is applied.
建物は地震などの外力に耐えられるように設計されている。
The building is designed to withstand external forces such as earthquakes.
外力なしに変化が起きることはない。
Change does not occur without an external force.
Compound of 外 ('outside; external') and 力 ('force; power'). A technical term from physics and engineering that also sees figurative use in social and political contexts.
USAGE:
- In physics, corresponds to the English term 'external force' — a force acting on a body from outside the system being analyzed.
- In structural engineering, 外力 includes forces like wind, earthquakes, and snow load that buildings must resist.
- Figuratively, can describe political, economic, or social pressure from outside: 外力による変革 ('reform driven by outside forces').
COMMON COLLOCATIONS:
- 外力が加わる: for external force to be applied
- 外力に耐える: to withstand external force
- 外力による変形: deformation caused by external force
- 外力なし: without external force
SIMILAR WORDS:
- 内力: internal force — force generated within a system or body
- 圧力: pressure — force per unit area; also used figuratively for political or social pressure
- 重力: gravity — the specific external force due to gravitational attraction
- 応力: stress (engineering) — the internal distribution of force within a material