Question

The mechanical advantage of a machine is 5 and its efficiency is 80%. It is used to lift a load of 200 kgf to a height of 20 m. Calculate a. the effort required b. the work done on the machine.(Take g =9.8m/s^2).

Answer 1

mechanical advantage, MA = 5

efficiency, η = 80%

load, W = 200 kgf

or W = 200 × 10 N

W = 2000 N

distance moved by load, y = 20 m

Effort, P =

W

MA

P = = 400 N

2000

5

Velocity ratio, VR =

MA

η

VR =

5

80

100

VR = 6. 25

Also, VR =

distance moved by effort (x)

distance moved by load (y)

6. 25 =

x

20

x = 125 m

Work done on machine, W' = P × x

W' = 400 × 125 = 50000 J

mark me as brainlist