Question

3.)

3A.) A 14-cm long nichrome wire is connected across the terminals of a 1.5 V battery. If the current in the wire is 1.4 A , what is the wire's diameter?

3B.) What is the resistance of A 90.0 cm long piece of carbon with a 0.700 mm ×× 0.700 mm square cross section?

Answer 1

A) given :

length = l = 14cm = 0.14 m

D = diameter = ?

i = current = 1.4 A

voltage applied = E = 1.5V

= resistivity of nichrome =

Resistance is given by .

using ohm's law :

[answer]

B) given :

= resistivity of nichrome =

l = length = 90 cm = 0.9 m

A = area =

therefore, Resistance = [answer]