Question

if 10 turns of wire is recoiled on a cylindrical reel of radius 3.5 cm find the length of the wire

Answer 1

Solution :-

The wire is recoiled on a cylindrical reel means we have to find the circumference of the circular portion of cylinder.

Circumference of circle (1 turn) = 2πr

⇒ 2*22/7*3.5

⇒ 154/7

= 22 cm

So, 22 cm wire will be needed to recoil the cylindrical reel in 1 turn.

For 10 turns, wire will be needed = 10*22

= 220 cm

Answer.

Answer 2

Find the wire used in 1 turn:

Circumference = 2πr

Circumference = 2π (3.5) = 22 cm

Find the wire used in 10 turns:

1 turn = 22 cm

10 turns = 22 x 10 = 220 cm

Answer: The length of the wire is 220 cm