Question

If in a system, the force of attraction between two point masses of $1kg$ each situated $1km$ apart is taken as a unit of force and is called notwen (Newton written in reverse order) and if $G=6.67\times {10}^{-11}N-m^{2}k{g}^{-2}$ in SI units then which of the following is true ?

• A. $1notwen=6.67\times {10}^{-11}newton$
• B. $1newton=6.67\times {10}^{-17}notwen$
• C. $1notwen=6.67\times {10}^{-17}newton$
• D. $1notwen=6.67\times {10}^{-12}newton$

Answer 1

The correct option is C $1notwen=6.67\times {10}^{-17}newton$

The force of attraction between two bodies is given by:

$F=G\frac{m_1{m}_2}{r^2}$

According to the question, the force between the two bodies of mass unit kg and kept at a distance of $1km$ is given by $1notwen$.

$1notwen=G\frac{1kg\times 1kg}{(1km{)}^2}$

$=\left(\begin{array}{c}\frac{6.67\times {10}^{-11}}{{10}^6}\end{array}\right)\left(\begin{array}{c}\frac{k{g}^2}{m^2}\end{array}\right)$

$=6.67\times {10}^{-17}newton$