A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of inclination of the...

      

A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of
inclination of the plane is 300 and its efficiency is 75%, determine:
a) The effort needed to move the load up the inclined plane at a constant velocity.
b) The workdone against friction in raising the mass through the height of 1.0m.

  

Answers


Moraa
a) The effort needed to move the load up the inclined plane at a constant velocity.
V.R=1/sin 30 =2
Therefore, (M.A/2)*20=75
M.A= (2*75)/20 =3/2
3/2 = 82N/effort
Effort= (82*2)/3 =540N
b) The workdone against friction in raising the mass through the height of 1.0m.
Work input=effort*effort distance = (540*4)/sin 30 =4320J
Work output=load*load distance= 81*2*4= 3240J
Therefore, workdone against friction= 4320-3240= 1180J
Moraa orina answered the question on April 9, 2018 at 16:54


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