Question

an aluminium has diameter 0.5 millimetre and resistivity is 2.8 × 10 to power 6 ohm how much length of this why is required to make a 10 ohm coil​

Answer 1

Resistance = resistivity × length/area

diameter = 0.5 mm = 0.05 cm = 5× 10^-4 m

radius = 2.5 × 10^-4

Area = pie r^2 = 3.14× 6.25 × 10^ -8

= 19.625× 10^-8

R = 2.8× 10^-6× L/ 19.625× 10^-8

R = 2.8 × 10^2 × L/19.625

10 × 19.625 = 2.8× 10^2 L

196.25/2.8 × 10^2 = L

70.08 × 10^-2m = L

0.7008 m= L

✌❤Dr.Dhruv❤✌