Physics
A pair of scissors is used to cut a piece of cloth by keeping it at a distance of 8.0 cm from its rivet and applying an effort of 10 kgf by fingers at a distance 2.0 cm from the rivet.
(a) Find: (i) the mechanical advantage of scissors and (ii) the load offered by the cloth.
(b) How does the pair of scissors act - as a force multiplier or as a speed multiplier?
Machines
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Answer
(a)
(i) We know that,
Given,
Load arm = 8.0 cm
Effort arm = 2 cm
Substituting the values in the formula we get,
(ii) We know,
Given,
Effort = 10 kgf
Substituting the values in the formula we get,
(b) As the mechanical advantage is less than 1 i.e. M.A. < 1. Hence, the pair of scissors acts as a speed multiplier as there is larger displacement of load than displacement of effort.
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