JEE Mains · Physics · STD 11 - 7. gravitation
Three masses 200 kg, 300 kg and 400 kg are placed at the vertices of an equilateral triangle with sides 20 m . They are rearranged on the vertices of a bigger triangle of side 25 m and with the same centre. The work done in this process _________ J.
- A \( 9.86\times10^{-6} \)
- B \( 2.85\times10^{-7} \)
- C \( 1.74\times10^{-7} \)
- D \( 4.77\times10^{-7} \)
Answer & Solution
Correct Answer
(C) \( 1.74\times10^{-7} \)
Step-by-step Solution
Detailed explanation
Work done by external agent : \(w _{ ext }=\Delta U\) \(U _{ i }=-\frac{ Gm _1 m_2}{ r _{ i }}-\frac{ Gm _2 m_3}{ r _{ i }}-\frac{ Gm _1 m_3}{ r _{ i }}: r _{ i }=20 m\)…
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