Question

When a body is weighed successively in the two pans of a physical balance with unequal arms, the apparent masses are found to be 4g and 9g. The ratio of the arm lengths will be –

• A. $\frac{4}{9}$
• B. $\frac{9}{4}$
• C. $\frac{2}{3}$
• D. $\frac{16}{81}$

Answer 1

Answer: (C)

$\frac{2}{3}$

Answer 2

$\frac { \ell _ { 1 } } { \ell _ { 2 } } = \sqrt { \frac { m _ { 1 } } { m _ { 2 } } }$

so, $\frac { \ell _ { 1 } } { \ell _ { 2 } } : \sqrt { \frac { 4 } { 9 } } = \frac { 2 } { 3 }$