Test Index

Volumes Practice Test 1

Question : 4 of 40

Marks: +1, -0

\mathrm{cm}^3

Solution: 👈: Video Solution

Concept:

When silver is drawn into a wire, its volume remains the same.

Explanation:

The wire is a cylinder.

Diameter

=1\ \mathrm{mm}=0.1\ \mathrm{cm}

, so radius

r=\frac{0.1}{2}=\frac{1}{20}\ \mathrm{cm}

Let the length of the wire be

L

Volume of wire

=\pi r^2 L

Given volume

=66\ \mathrm{cm}^3

So,

\pi \left(\frac{1}{20}\right)^2 L=66

Using

\pi=\frac{22}{7}

\frac{22}{7}\times\frac{1}{400}\times L=66

L=\frac{66\times400\times7}{22}

L=8400\ \mathrm{cm}

Convert to metres:

L=\frac{8400}{100}=84\ \mathrm{m}

Answer:

The length of the wire is

84\ \mathrm{m}

So, the correct option is B.

Go to Question:

Prev Question

Next Question