66 cubic centimetres of silver is drawn into a wire 1 mm in diameter. The length of the wire in metres will be:
84
90
168
336
Explanation:
Let the length of the wire be h.
Radius = $\dfrac{1}{2}mm = \dfrac{1}{20}cm$. Then,
=> $\dfrac{22}{7} \times \dfrac{1}{20} \times \dfrac{1}{20} \times h = 66$
=> h =$ (\dfrac{66 \times 20 \times 20 \times 7}{22}) = 8400cm = 84 m$
Let the length of the wire be h.
Radius = $\dfrac{1}{2}mm = \dfrac{1}{20}cm$. Then,
=> $\dfrac{22}{7} \times \dfrac{1}{20} \times \dfrac{1}{20} \times h = 66$
=> h =$ (\dfrac{66 \times 20 \times 20 \times 7}{22}) = 8400cm = 84 m$