Login/Sign Up
Q16. a) Give two examples of substances which are good conductors of electricity. Why do you think they are good conductors of electricity? b) Calculate the resistance of a copper wire 1.0km long and 0.50mm diameter if the resistivity of copper is 1.7×10-8Ωm.
Q16. a) Give two examples of substances which are good conductors of electricity. Why do you think they are good conductors of electricity? b) Calculate the resistance of a copper wire 1.0km long and 0.50mm diameter if the resistivity of copper is 1.7×10-8Ωm.
CBSE | Class 10 | Electricity | Lakhmir Singh | Physics
Q16. a) Give two examples of substances which are good conductors of electricity. Why do you think they are good conductors of electricity? b) Calculate the resistance of a copper wire 1.0km long and 0.50mm diameter if the resistivity of copper is 1.7×10-8Ωm.

Answer:

a) Two examples of substances that are good conductors of electricity are silver and copper. These two metals have free electrons that are available for conduction.

b) Given in question :

l = 1km = 1000m

r = d/2

= 0.5/2mm

= 0.25mm

= 0.25×10-3m

ρ = 1.7×10-8Ωm

We know that,

R = ρl/A

R = 86.6Ω

i

More Material