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Question
A fire tongs has arms 20 cm long. It is used to lift a coal of weight 1.5 kgf by applying an effort at a distance 15 cm from the fulcrum. Find:
- the mechanical advantage of fire tongs and
- the effort needed.
Solution
M.A. =?
Effort arm = 15 cm
Load arm = 20 cm
M.A. = `"Effort arm"/"load arm"`
M.A. = `15/20`
M.A. = `3/4`
M.A. = 0.75
Effort = ?
Effort = `"Load"/"M.A." = 1.5/0.75` = 2.0 kgf
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