JEE Mains · Physics · STD 11 - 7. gravitation
Assuming the earth to be a sphere of uniform mass density, the weight of a body at a depth \(d=\frac{R}{2}\) from the surface of earth, if its werght on the surface of earth is \(200\,N\), will be \(...........\,N\) ( \(Given R =\) Radrus of earth)
- A \(400\)
- B \(500\)
- C \(300\)
- D \(100\)
Answer & Solution
Correct Answer
(D) \(100\)
Step-by-step Solution
Detailed explanation
\(M =\frac{ W }{ g }=\frac{200}{10}=20\,kg\) Acc. due to gravity at a depth \(g^{\prime}= g \left(1-\frac{ d }{ R }\right)\) \(d \rightarrow\) depth from surface \(d =\frac{ R }{2}\) \(g ^{\prime}= g \left(1-\frac{ R / 2}{ R }\right)=\frac{ g }{2}=5 m / s ^2\) weight…
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