How does the peak stress induced by a sudden load compare to a gradual load application________________?
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Answer: C. two times
Explanation
A suddenly applied load transfers kinetic energy that instantaneously doubles the maximum strain and stress. Gradual loading allows the material to deform slowly while internal resistance builds up alongside the load. Dynamic impact factor for a sudden load equals two, resulting in peak stress twice as high as static loading. Dynamic loading conditions can induce much higher stresses than equivalent static forces due to shock effects. Strain energy absorbed by a material during sudden loading accommodates the instantaneous kinetic energy transfer. Machine parts subject to shock loads are designed with higher safety factors to prevent unexpected failure.
Crane hooks and lifting chains experience sudden load spikes when loads are picked up abruptly. Automotive crash structures are engineered to absorb sudden kinetic energy loads safely without fracturing. Mechanical designers apply a dynamic load factor to account for sudden stress surges in operation. Option A is incorrect because sudden application doubles the peak stress compared to gradual loading. Option B incorrectly halves the stress, ignoring the amplification caused by sudden energy transfer. Option D overestimates the dynamic stress magnification factor for a standard sudden load application.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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