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7. gravitation — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics7. gravitation1 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.
  • ✓
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: C.
If the Assertion is correct but Reason is incorrect.
c
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 $9.8 \mathrm{m} / \mathrm{s}^{2} .$ It is non zero.

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