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Two bulbs are working in parallel order....

Two bulbs are working in parallel order. Bulb A is brighter than bulb B . If `R_(A)` and `R_(B)` are their resistance respectively then

A

`R_(A)=R_(B)`

B

`R_(B)gt R_(A)`

C

`R_(A)gtR_(B)`

D

None of these

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AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will analyze the relationship between the power consumed by the bulbs and their resistances. ### Step 1: Understand the arrangement of the bulbs Two bulbs, A and B, are connected in parallel. In a parallel circuit, the voltage across each component is the same. **Hint:** Remember that in a parallel circuit, the voltage across each bulb is equal. ### Step 2: Recall the formula for power The power (P) consumed by an electrical device can be expressed using the formula: \[ P = \frac{V^2}{R} \] where \( V \) is the voltage across the device and \( R \) is its resistance. **Hint:** Power is directly related to voltage and inversely related to resistance. ### Step 3: Compare the power of the bulbs According to the problem, bulb A is brighter than bulb B. Since brightness is directly proportional to the power consumed, we can write: \[ P_A > P_B \] This means that the power consumed by bulb A is greater than that consumed by bulb B. **Hint:** Brightness indicates higher power consumption. ### Step 4: Relate power to resistance Using the power formula, we can express the powers of the bulbs in terms of their resistances: \[ P_A = \frac{V^2}{R_A} \] \[ P_B = \frac{V^2}{R_B} \] Since \( P_A > P_B \), we can substitute the power expressions: \[ \frac{V^2}{R_A} > \frac{V^2}{R_B} \] **Hint:** Since voltage is constant for both bulbs, you can simplify the inequality. ### Step 5: Simplify the inequality By canceling \( V^2 \) from both sides (assuming \( V \neq 0 \)): \[ \frac{1}{R_A} > \frac{1}{R_B} \] This implies: \[ R_B > R_A \] **Hint:** An inverse relationship indicates that if one quantity increases, the other must decrease. ### Step 6: Conclusion Since \( R_B > R_A \), we conclude that bulb B has a greater resistance than bulb A. Therefore, the bulb that is brighter (bulb A) has a lower resistance. **Final Answer:** \( R_B > R_A \)
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