Answer:
Explanation:
The velocity ratio of a wheel and axle is the ratio of the radius (R) of the wheel to the radius (r) of the axle. It is expressed as;
VR = R/r
Since radius = diameter/2
VR = (D/2)/(d/2)
VR = D/d
D is the diameter of the wheel and 'd' is the diameter of the axle.
Given VR = 3 and d = 5cm
3 = D/5
D = 15 cm
<em>If the diameter of the wheel is 15cm, the radius of the wheel will be 15/2 = 7.5cm.</em>
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<em>b) Workdone by the load = Load * distance moved by load</em>
<em>G</em><em>iven load = 60kg</em>
Distance moved by load = 2π*radius of axle
Distance moved by load = 2π(0.025) = 0.157
<em>workdone by load = 60*</em> 0.157 = 9.42J
Effort = Workdone by load/distance moved by the wheel
Effort = 9.42/2π(0.075)
Effort = 9.42/0.471
Effort = 20kg
<em>Hence the effort applied is 20kg</em>
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c) MA = Load/Effort
MA = 60/20
MA = 3
d) Efficiency = MA/VR * 100%
Efficiency = 3/3 * 100%
Efficiency = 100%
