JEE Mains · Physics · STD 11 - 7. gravitation
The ratio of the weights of a body on the Earth's surface to that on the surface of a planet is \(9 : 4\). The mass of the planet is \(\frac{1}{9}^{th}\) of that of the Earth. If \('R'\) is the radius of the Earth, what is the radius of the planet ? (Take the planets to have the same mass density)
- A \(\frac{R}{3}\)
- B \(\frac{R}{4}\)
- C \(\frac{R}{9}\)
- D \(\frac{R}{2}\)
Answer & Solution
Correct Answer
(D) \(\frac{R}{2}\)
Step-by-step Solution
Detailed explanation
Since mass of the object remains same \(\therefore \) Weight of object will be proporational to \('g'\) \((acceleration\, due\, to\,gravity)\) Given ; \(\frac{{{W_{earth}}}}{{{W_{planet}}}} = \frac{9}{4} = \frac{{{g_{earth}}}}{{{g_{planet}}}}\) Also,…
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