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a) The total velocity ratio of the system.
Combined V.R=V.R1*V.R2
V.R1=No. of teeth of driven gear/ No. of teeth of driving gear
= 20/25= 4
V.R2=60/30= 2
Hence, V.R= 4*2= 8
b) The mechanical advantage of the system if its efficiency is 85%.
Efficiency= (M.A/8)*20= 85
M.A= (85*8)/20= 5.8
Moraa orina answered the question on April 9, 2018 at 17:00
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