Physics
Assertion (A) : A bucket filled with water is heavier till it is immersed in water in well.
Reason (R) : The effect of upthrust is that the weight of body immersed in liquid appears to be lighter than its actual weight.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Fluids Upthrust
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Answer
assertion is false but reason is true
Explanation
Assertion (A) is false because when a bucket is lowered into a well, as it gets immersed in the water, it experiences an upward buoyant force (upthrust) which reduces its apparent weight, so the bucket feels lighter till it is immersed in water in well and once it is taken outside the water it gets heavier due to absence of upthrust.
Reason (R) is true because this is the definition of buoyancy which states that the upthrust reduces the apparent weight of the object in the fluid.
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