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2. motion in straight line — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysics2. motion in straight line1 Mark
MCQ
$Assertion$ : In a free fall, weight of a body becomes effectively zero.

$Reason$ : Acceleration due to gravity acting on a body having free fall is zero.

  • A
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If both the Assertion and Reason are incorrect.
  • ✓
    If the Assertion is correct but Reason is incorrect.
✓

Answer

Correct option: D.
If the Assertion is correct but Reason is incorrect.
d
In a free fall, effective weight of a body becomes zero. The reason behind it is the normal force acting on the object is equal to $mg$ which is same as the weight of the object. So, the object feels weightless. Actual weight during free fall is $mg$.

The acceleration due to gravity on the object falling down is $9.8\; m / s ^{2}$. It is non zero.

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