Question

Two spheres each of mass ${10}^{5}kg$ and radius $10m$ are kept in contact. Find the force of gravitation acting between them.

• A. $5.67\times {10}^{-3}N$
• B. $6.67\times {10}^{-3}N$
• C. $3.67\times {10}^{-3}N$
• D. $2.67\times {10}^{-3}N$

Answer 1

The correct option is B $6.67\times {10}^{-3}N$

$m_1=m_2={10}^{5}kg$

$r=10m$

$\therefore F=\frac{{Gm}_1{m}_2}{r^2}=\frac{{6\cdot 67\times 10}^{-11}\times {10}^5\times {10}^5}{{10}^2}$

$=6\cdot 67\times {10}^{-3}N$