A student in Trinidad investigates different simple machines. Which statement correctly explains why the efficiency of a real machine is always less than 100%?

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Question

A student in Trinidad investigates different simple machines. Which statement correctly explains why the efficiency of a real machine is always less than 100%?

Accepted Answer

Energy is lost due to friction — Award 1 mark for identifying friction as the cause of energy loss. A is incorrect — MA can vary regardless of efficiency. C is incorrect — VR can be less than 1 in some machines. D is incorrect — while true for real machines, this is a consequence, not the cause.

Answer

Mechanical advantage cannot exceed velocity ratio

Answer

Energy is lost due to friction

Answer

The velocity ratio is always greater than 1

Answer

The load is always greater than the effort

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