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. (Gravitational constant G=6.7×10−11 N m2/kg2)
Held on 24 Jan 2026 · Verified 6 Jul 2026.
2.85×10−7
4.77×10−7
1.74×10−7
9.86×10−6
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