The velocity ratio of a machine is 5 and it efficiency is 75%.what effort would be needed to lift a load of 25N with the machine?
Calculate for M.A first
Then, get ur M.A as 3.75
And M.A = load ÷effort
E= 6.666N
OR
E ≈6.67N
(25/5) / .75
e = L/E * 1/Vr = 0.75,
25/E * 1/5 = 0.75,
e = efficiency.
E = effort in Newtons.
Vr = velocity ratio.
80%/5=2000N
To find the effort needed to lift a load using a machine, we need to make use of the concepts of velocity ratio and efficiency.
First, let's start by understanding the velocity ratio. The velocity ratio of a machine is the ratio of the distance moved by the effort to the distance moved by the load. It is denoted by VR.
Given that the velocity ratio of the machine is 5, it means that for every 5 units of distance moved by the effort, the load will move 1 unit of distance.
Next, let's consider efficiency. Efficiency is the measure of how effectively a machine converts the input (effort) into output (load). It is expressed as a percentage.
Given that the efficiency of the machine is 75%, it means that the machine is capable of converting 75% of the input effort into the output force. So, only 75% of the effort will be effective in lifting the load.
Now, let's calculate the effort needed to lift the load of 25N using the machine.
Since the machine has a velocity ratio of 5, it means that for every 5 units of distance moved by the effort, the load will move 1 unit of distance. In other words, the effort will need to move 5 times the distance compared to the load.
So, the mechanical advantage (MA) of the machine is 5, which is equal to the velocity ratio.
The formula for mechanical advantage is MA = Load / Effort.
We know that the load is 25N. Let's assume the effort needed is E, so we have:
5 (velocity ratio) = 25 / E
Simplifying the equation, we get:
E = 25 / 5
E = 5 N
So, the effort needed to lift the load of 25N using the machine would be 5N.
However, we also need to consider the efficiency of the machine. As mentioned earlier, the efficiency is 75%.
To calculate the effort needed, accounting for efficiency, we need to divide the required effort by the efficiency:
Effort needed with efficiency considered = Effort needed / (Efficiency / 100)
Effort needed with efficiency considered = 5 N / (75 / 100)
Effort needed with efficiency considered = 5 N / 0.75
Effort needed with efficiency considered = 6.67 N
Therefore, the effort required to lift the load of 25N using the machine, accounting for the efficiency of 75%, would be approximately 6.67N.