Assertion (A) : By using freewheeling diode, load performance becomes ...
By using freewheeling diode, load performance becomes better because load current waveform is improved.
Whenever load voltage tends to go negative, freewheeling comes into play as a result of which ioaa current is transferred from main thyristor to freewheeling diode, allowing the thyristor to regain its forward blocking capability.
Hence, both assertion and reason are true but reason is not the correct explanation of assertion.
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Assertion (A) : By using freewheeling diode, load performance becomes ...
Explanation:
The assertion (A) states that the load performance becomes better by using a freewheeling diode, while the reason (R) states that the freewheeling diode prevents the load voltage from becoming negative.
A is true:
When an inductive load is connected to a switching device, such as a relay or a transistor, the load generates a back EMF (electromotive force) when the current is interrupted. This back EMF can cause a voltage spike, which can damage the switching device. Moreover, the energy stored in the inductive load needs to be dissipated in a controlled manner.
By using a freewheeling diode, also known as a flyback diode or a snubber diode, the load performance can be improved. The freewheeling diode provides a path for the inductive load current to circulate when the switching device is turned off. It allows the current to decay gradually and prevents voltage spikes by providing a low resistance path for the energy stored in the inductive load to dissipate.
R is true:
One of the main functions of the freewheeling diode is to prevent the load voltage from becoming negative. When the switching device is turned off, the inductive load tries to maintain the current flowing through it. If there is no freewheeling diode, the load voltage can become negative, which can lead to various issues such as arcing, damage to the switching device, or malfunction of the load.
The freewheeling diode conducts when the switching device is turned off, providing a path for the inductive load current. This prevents the load voltage from becoming negative and ensures that the load is protected.
Reason (R) is not the correct explanation of Assertion (A):
While the reason (R) correctly states that the freewheeling diode prevents the load voltage from becoming negative, it does not provide a direct explanation of why the load performance becomes better. The improved load performance is mainly due to the controlled dissipation of energy in the inductive load, which is achieved by the freewheeling diode.
Therefore, both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
Conclusion:
The correct answer is option 'B': Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
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