Question 287: Units , Dimensions and Error Analysis

Question

Length, breadth and thickness of a strip having a uniform cross section are measured to be
10.5 cm
,
0.05 mm
, and
6.0 μm
, respectively. Which of the following option(s) give(s) the volume of the strip in cm
3
with correct significant figures:

Accepted Answer

$$ \begin{aligned} & l=10.5 \mathrm{~cm} ightarrow 3 \mathrm{SF} \ & b=0.05 \mathrm{~mm}=5 	imes 10^{-3} \mathrm{~cm} ightarrow 1 \mathrm{SF} \ & h=6.0 \mu \mathrm{~m}=6.0 	imes 10^{-4} \mathrm{~cm} ightarrow 2 \mathrm{SF} \end{aligned} $$
we know, $V=$ lbh
$$ \begin{aligned}So\,\,\,\, v & =10.5 	imes 5 	imes 10^{-3} 	imes 6.0 	imes 10^{-4} \ & =315 	imes 10^{-7} \mathrm{~cm}^3 \ & =3.15 	imes 10^{-5} \mathrm{~cm}^3 \end{aligned} $$
The final answer should have the same number of significant figures as the factor with the fewest significant figures.
$$ 	ext { So } V=3 	imes 10^{-5} \mathrm{~cm}^3 \quad ightarrow 1 \mathrm{SF} $$

Answer

$3.2 	imes 10^{-5}$

Answer

$32.0 	imes 10^{-6}$

Answer

$3.0 	imes 10^{-5}$

Answer

$3 	imes 10^{-5}$

Units , Dimensions and Error Analysis

Length, breadth and thickness of a strip having a uniform cross section are measured to be 10.5 cm , 0.05 mm , and 6.0 μm , respectively. Which of the following option(s) give(s) the volume of the strip in cm 3 with correct significant figures:

Choose the correct answer: