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Question
(a) Observe the diagram given below and state whether the bulb will glow or not when we switch on K.
(b) Is it safe to handle the bulb when the switch is OFF?
(c) Give a reason for your answer in (b).
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Solution
- In the given figure it is observed that the bulb is connected with Live wire and the key is connected with Neutral wire. When the key or switch is ON, the path of current flow is completed, hence the bulb will glow.
- It is NOT safe to handle the bulb when the switch is OFF as bulb is directly connected to live wire.
- In the OFF position, the bulb remains connected to the high potential terminal through the live wire, but no current flows through the bulb, as the return path is incomplete. In this condition, it is not safe to touch the bulb even from outside. As a result, if the switch is connected to the neutral wire, it might be deceiving and even harmful to the user.
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