THE VELOCITY RATIO OF A MACHINE IS 5 AND ITS EFFICIENCY IS 75%. WHAT EFFORT WOULD BE NEEDED TO LIFT A LOAD OF 150N WITH THE MACHINE

The answer to the question is: C. 40N

To calculate the effort needed to lift a load using a machine, we can use the formula:

Efficiency = (Actual Mechanical Advantage / Velocity Ratio) x 100

Where, Efficiency = 75% or 0.75

Velocity Ratio = 5

We can rearrange the formula to solve for Actual Mechanical Advantage:

Actual Mechanical Advantage = (Efficiency / 100) x Velocity Ratio

Given that the load to be lifted is 150N, we can use the formula for mechanical advantage:

Mechanical Advantage = Load / Effort

Rearranging this formula to solve for Effort:

Effort = Load / Mechanical Advantage

Substituting the values into the equation:

Effort = 150N / Actual Mechanical Advantage

Now, let’s calculate the actual mechanical advantage using the given velocity ratio and efficiency.

Actual Mechanical Advantage = (0.75 / 100) x 5

                        = 0.75 x 5
                        = 3.75

Now, we can calculate the effort needed to lift the load:

Effort = 150N / 3.75 = 40N