Physics-
General
Easy
Question
The following figure shows two air-filled bulbs connected by a U-tube partly filled with alcohol. What happens to the levels of alcohol in the limbs X and Y when an electric bulb placed midway between the bulbs is lighted
- The level of alcohol in limb X falls while that in limb Y rises
- The level of alcohol in limb X rises while that in limb Y falls
- The level of alcohol falls in both limbs
- There is no change in the levels of alcohol in the two limbs
The correct answer is: The level of alcohol in limb X falls while that in limb Y rises
Black bulb absorbs more heat in comparison with painted bulb. So air in black bulb expands more. Hence the level of alcohol in limb X falls while that in limb Y rises
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