First slide

Fluid statics

Question

Two bodies are in equilibrium when suspended in water from the arms of a balance. The mass of one body is 36 g
and its density is 9 g / ${cm}^{3}$ . If the mass of the other is 48g, its density in $g / {cm}^{3}$ is

Moderate

A

$\frac{4}{3}$
B

$\frac{3}{2}$
C

3
D

5

Solution

Apparent weight = V ( $ρ - σ$ )g = $\frac{m}{ρ} (ρ - σ) g$
where m = mass of the body,
$ρ$ = density of the body
$σ = density of water$
If two bodies are in equilibrium then their apparent weight must be equal.
$∴ \frac{m_{1}}{ρ_{1}} (ρ_{1} - σ) = \frac{m_{2}}{ρ_{2}} (ρ_{2} - σ)$
$\Rightarrow \frac{36}{9} (9 - 1) = \frac{48}{ρ_{2}} (ρ_{2} - 1)$
By solving we get $ρ_{2} = 3$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App