NEET Physics Question - Current Electricity - Power of Electrical Circuit

Assertion (A): The rate at which energy is being delivered to a light bulb is lower after it has been on for a few seconds than just after it is turned on.

Reason (R): As the filaments warms up, its resistance rises and the current falls.

Both (A) & (R) are true and the (R) is the correct explanation of the (A)

Both (A) & (R) are true but the (R) is not the correct explanation of the (A)

(A) is true but (R) is false

Both (A) and (R) are false

Solution:

Initially, the bulb's cold filament has lower resistance. As it heats up, resistance increases, causing current to drop (for a constant voltage source). Since power \(P = V^2/R\), an increase in \(R\) leads to a decrease in \(P\). Therefore, both assertion and reason are true, and the reason correctly explains the assertion.

Rankers Physics

Energy Delivery to Light Bulb

Solution:

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