Question

A copper rod of diameter 1 cm and length 8 cm is drawn into a wire of length 18 m of uniform thickness. Find the thickness of wire​

Answer 1

Answer:

The volume of the rod = π×(

2

1

)

2

×8=2π cm

3

The length of the new wire of the same volume = 18 m = 1800 cm

If r is the radius ( in cm ) of cross-section of the wire, its voume = π×r

2

×1800 cm

3

Therefore,

π×r

2

×1800=2π

r

2

=

900

1

r=

30

1

So, the diameter of the cross section, i.e., the thickness of the wire is

15

1

cm, i.e., 0.67 mm (approx.)

Step-by-step explanation:

छड़ का आयतन = π×(2 1) 2 ×8=2π 3 उसी आयतन के नए तार की लंबाई = 18 m = 1800 cm 3 है, इसलिए π×r 2 ×1800=2π 2 r= 301 होते हैं, अर्थात क्रॉस सेक्शन का व्यास, I, तार की मोटाई 15 1 सेमी है, यानी, 0.67 मिमी (लगभग।)

Answer 2

$\huge\boxed{\fcolorbox{cyan}{red}{Hello!}}$

The copper rod is in the form of a cylinder -

Diameter of rode= 1 cm

So,Radius=

$\frac{1}{2} \: cm$

Height = 8 cm

Volume of copper rod =

${\pi}r^{2} h$

So, Volume of copper rod =

${2\pi \: cm}^{3}$

Now,

Radius of wire = r

Height = 1800 cm

Volume of wire=

${1800\pi}r ^{2}$

Volume of copper rod = Volume of wire

${1800\pi}r^{2} = 2\pi \\ {1800r}^{2} = 2 \\ {r}^{2} = \frac{1}{900} \\ r = \frac{1}{30}$

Thickness of wire = Diameter of wire

2 r

$2 \times \frac{1}{30} \\ \frac{1}{15} cm$

Thickness of wire = 1/15 cm

Hope it helps you..