What is a body's inherent resistance to any change in its state of rest or uniform motion called_______________?
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Answer: C. inertia
Explanation
Inertia is defined as the natural tendency of an object to resist changes in its velocity. Mass serves as the quantitative measure of this inherent resistance in translational motion. An external force is required to overcome inertia and accelerate any stationary or moving body. Newton's first law of motion establishes the foundational concept of inertia in classical mechanics. Rotational inertia, or moment of mass, resists changes in angular velocity around an axis. Dynamic balancing calculations account for inertial forces to minimize vibration in rotating machinery.
Automotive seatbelts protect passengers by restraining bodies when vehicle inertia causes forward motion. Flywheels store kinetic energy using rotational inertia to smooth out power pulses in piston engines. Engineers must account for inertial loads when designing high-speed robotic arms and machinery. Option B represents friction, which is a contact force resisting relative sliding between surfaces. Option D refers to general resisting forces rather than the intrinsic property of mass inertia. Option E describes resisting torque associated with rotational friction or load resistance.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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