Question

A lever of length 1m has been used to lift a load of 600N by applying an effort of 200N. If load is at 20cm from fulcrum, calculate mechanical advantages, velocity ratio and efficiency

solve numerical problem ​

Answer 1

Step-by-step explanation:

The length of the lever = 1 m

The weight of the load (force output), F_rF

r

= 600 N

The effort applied (force input), F_eF

e

= 200 N

1) The Mechanical Advantage, MA of the lever is given as follows;

MA = \dfrac{F_r}{F_e} = \dfrac{600 \ N}{200 \ N} = 3MA=

F

e

F

r

The length of the lever = 1 m

The weight of the load (force output), F_rF

r

= 600 N

The effort applied (force input), F_eF

e

= 200 N

1) The Mechanical Advantage, MA of the lever is given as follows;

MA = \dfrac{F_r}{F_e} = \dfra

=

200 N

600 N

=3

The Mechanical Advantage, MA of the lever = 3

2) The velocity ratio, V.R., is the ratio of the distance moved by the effort, L_eL

e

, to the distance moved by the load, L_rL

r

For the lever, we have;

The distance of the load from the fulcrum, L_rL

r

= 20 cm = 0.2 m

Therefore, we have;

The distance of the effort from the fulcrum, L_eL

e

= 1 m - 0.2 m = 0.8 m

From which we have;

V.R.= \dfrac{L_e}{L_r} = \dfra

The distance of the load from the fulcrum, L_rL

r

= 20 cm = 0.2 m

Therefore, we have;

The distance of the effort from t

V.R.= \dfrac{L_e}{L_r} = \dfrac{0.8

L

e

=

0.2 m

0.8 m

=4

The velocity ratio of the lever = 4

3) The efficiency, η, is given as follow;

\%Efficiency, \, \eta = \dfrac{M.A.}{V.R.} \times 100 = \dfrac{3}{4} \times 100 = 75\%%Efficiency,η=

V.R.

M.A.

×100=

4

3

×100=75%

The efficiency of the lever is 0.75 or 75

Answer 2

1) The Mechanical Advantage of the lever is 3

2) The velocity ratio of the lever is 4

3) The efficiency of the lever is 75%

Step-by-step explanation:

A lever is a simple machine that is used to lift a heavy load with a little effort or force

The mechanical advantage is the ratio of the force output to the force input

The given parameters of the lever are;

The length of the lever = 1 m

The weight of the load (force output),
`F_r` = 600 N

The effort applied (force input),
`F_e` = 200 N

1) The Mechanical Advantage, MA of the lever is given as follows;

`MA = (F_r)/(F_e) = (600 \ N)/(200 \ N) = 3`

The Mechanical Advantage, MA of the lever = 3

2) The velocity ratio, V.R., is the ratio of the distance moved by the effort,
`L_e`, to the distance moved by the load,
`L_r`

For the lever, we have;

The distance of the load from the fulcrum,
`L_r` = 20 cm = 0.2 m

Therefore, we have;

The distance of the effort from the fulcrum,
`L_e` = 1 m - 0.2 m = 0.8 m

From which we have;

`V.R.= (L_e)/(L_r) = (0.8 \ m)/(0.2 \ m) = 4`

The velocity ratio of the lever = 4

3) The efficiency, η, is given as follow;

`\%Efficiency, \, \eta = (M.A.)/(V.R.) * 100 = (3)/(4) * 100 = 75\%`

The efficiency of the lever is 0.75 or 75%.