Question

In making an alloy, a substance of specific gravity $m _ { 1 }$ is mixed with another substance of specific gravity $m _ { 2 }$; then the specific gravity of the alloy is

• A. $\left( \frac { m _ { 1 } + m _ { 2 } } { s _ { 1 } + s _ { 2 } } \right)$
• B. $\left( \frac { s _ { 1 } s _ { 2 } } { m _ { 1 } + m _ { 2 } } \right)$
• C.
• D.

Answer 1

Answer: (C)

Answer 2

Specific gravity of alloy $= \frac { \text { Density of alloy } } { \text { Density of water } }$

$= \frac { \text { Mass of alloy } } { \text { Volume of alloy } \times \text { density of water } }$

$= \frac { m _ { 1 } + m _ { 2 } } { \frac { m _ { 1 } } { \rho _ { 1 } / \rho _ { w } } + \frac { m _ { 2 } } { \rho _ { 2 } / \rho _ { w } } } = \frac { m _ { 1 } + m _ { 2 } } { \frac { m _ { 1 } } { s _ { 1 } } + \frac { m _ { 2 } } { s _ { 2 } } }$

$\left[ \right.$ As specific gravity of substance $\left. = \frac { \text { density of substance } } { \text { density of water } } \right]$