Physics · Basic concepts of rotational motion, moment of a force, torque, angular momentum, conservation of angular momentum and its applications

is applied to unwind a screw.

is applied to unwind a screw.

  • A. single force
  • B. Couple
  • C. Parallel force
  • D. None of these

Step-by-step solution

Unwinding a screw requires a turning effect (torque). A couple consists of two equal and opposite forces with a perpendicular distance between them, producing pure rotation without translation, which is ideal for unscrewing. A single force would cause translation or require an off-center application, but the typical mechanism (like a screwdriver) applies a couple.
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