Question

A sting is wound around a pencil 50 times .The total width of all turns is 5cm.Find the thickness of the string

Answer 1

Step 1: Given :
$$\begin{gathered} \mathrm{number}\mathrm{of}\mathrm{turns}=50 \\ \mathrm{total}\mathrm{width}\mathrm{of}\mathrm{all}\mathrm{turns}=5\mathrm{cm} \\ \mathbf{Step}\mathbf{}\mathbf{2}\mathbf{:}\mathbf{}\mathbf{finding}\mathbf{}\mathbf{thickness}\mathbf{}\mathbf{of}\mathbf{}\mathbf{the}\mathbf{}\mathbf{string} \\ \mathrm{We}\mathrm{can}\mathrm{find}\mathrm{thickness}\mathrm{of}\mathrm{the}\mathrm{dtring}\mathrm{as}\mathbf{,} \\ \mathrm{Thickness}\mathrm{of}\mathrm{the}\mathrm{string}=\frac{\mathrm{total}\mathrm{width}\mathrm{of}\mathrm{all}\mathrm{turns}}{\mathrm{number}\mathrm{of}\mathrm{turns}} \\ \Rightarrow \frac{5}{50}=0.1\mathrm{cm}\mathrm{or}1\mathrm{mm} \end{gathered}$$

Hence, thickness of string is 1 mm