Correct Answer - Option 4 : Automatic washing machine
Explanation:
Sensitivity: The parameters of a control system are always changing with the change in surrounding conditions, internal disturbance, or any other parameters.
This change can be expressed in terms of sensitivity. Any control system should be insensitive to such parameters but sensitive to input signals only.
Now there are two types of control systems:
1. Open-loop control system
2. Closed-loop control system
Open-loop control system:
1. A control system in which the control action is totally independent of the output of the system. A manual control system is also an open-loop control system.
2.The sensitivity function for the overall open loop system is one.
Closed-loop system:
1. Control systems in which the output has an effect on the input quantity in such a manner that the input quantity will adjust itself based on the output generated
2. The sensitivity function for the closed-loop function is:
\(S=\frac{1}{1 \ + \ G(s)H(s)}\)
Hence the sensitivity of the closed-loop system is reduced by a factor (1 + G(s)H(s)) as compared to the open-loop system.
An automatic Washing Machine is an example of an open-loop system as the machine runs according to the pre-set time irrespective of washing is completed or not.
Automatic intensity adjustable light bulb is an example of a closed-loop system that controls the light intensity automatically as required depending on the daylight conditions with the help of feedback sensors connected to it.
Hence an automatic Washing Machine is more sensitive to the variation in system's gain as compared to an automatic intensity adjustable light bulb.
Hence option (4) is the correct answer.
