# What is the thickness of an iron plate that has a mass of 0.25*g, and an area of 25*cm^2. rho_"iron"=19*g*cm^-2?

May 15, 2017

$\text{Thickness} \cong 0.005 \cdot m m$

#### Explanation:

I think you are one the right track........

${\rho}_{\text{density"="mass"/"volume}}$

And of course, $\text{volume} = l \times b \times w$, where $l = \text{length}$, $b = \text{breadth}$, and $w = \text{width}$ ($\text{lbw"!="leg before wicket}$).

So, $\text{volume"="mass"/rho_"density} = l \times b \times w$

And thus w("width")="mass"/(rhoxxlxxb)

$= \frac{0.25 \cdot g}{19 \cdot g \cdot c {m}^{-} 3 \times 25 \cdot c {m}^{2}} = 5.26 \times {10}^{-} 4 \cdot \frac{1}{\frac{1}{\text{cm}}}$

$5.26 \times {10}^{-} 4 \cdot c m \equiv 5.26 \times {10}^{-} 3 \cdot m m$