Ten identical lengths of wire are laid closely

side-by-side. their combined width is measured

and found to be 14.2 mm. calculate:

a the radius of a single wire

b the volume in mm of a single wire if its

length is 10.0 cm (volume of a cylinder =

tr’h, where r=radius and h= height).

can you find b

Explanation:

a) Calculate the radius of a single wire

Since ten identical lengths of wire are laid closely, the combined width is equal to the sum of the diameters of the ten wires.

That is:

From which you can solve for the diameter of a single wire:

The radius is half the diameter, so:

b) Calculate the volume in mm of a single wire if its length is 10.0 cm

The shape of one wire is cylindrical. So, the formula for the volume is:

Where r is the radius and L is the length.

Since the width is given in mm, conver the length to mm too.

And subsituting the values in the formula of the volume you get:

That must  be rounded to 3 significant figures: 158 mm³.