Question

A cylinder of material is 10cm long and has a cross section of 2cm.cm .if it's resistance along the wire length be 20 ohm. what will be its resistivity in no and units.

Answer 1

Answer:

0.04 rho

Explanation:

Length = 0.1 metres

Area of cross section = 0.0002 metre sq.

resistance = 20 ohm

RESISTIVITY=RESISTANCE X AREA / LENGTH

resistivity= 20 x 0.0002 / 0.1

              = 0.04 rho

Answer 2

Given :

Length (L) = 10 cm

Area of cross section (A) = 2 cm²

Resistance (R) = 20 Ω

To Find :

The resistivity of the wire.

Solution :

Let 'ρ' be the resistivity of the wire.

The formula for resistance of the wire is ρ$\frac{L}{A}$

Where, L = Length and A = Area of cross-section of the wire.

∴  Resistance  = ρ $\frac{L}{A}$

⇒       20         = ρ × $\frac{10}{2}$

⇒        ρ          =  4 ohm.cm        

Therefore, The resistivity of the wire is 4 ohm.cm