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प्रश्न
Figure below shows a wheel barrow of mass 15 kgf carrying a load of 30 kgf with its centre of gravity at A. The points B and C are the centre of wheel and tip of the handle such that the horizontal distance AB = 20 cm and AC = 40 cm.
Find:
- the load arm,
- the effort arm,
- the mechanical advantage and
- the minimum effort required to keep the leg just off the ground.
उत्तर
Total load = 15 + 30 = 45 kgf
In diagram
(a) Load arm = 20 cm
(b) Effort arm = 20 + 40 = 60 cm
(c) M.A. = `60/20 = 3`
(d) E = `"Load"/"M.A."`
= `45/3`
= 15 kgf
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