What is the resistance of a 20.0-meter-long
tungsten rod with a cross-sectional area of
1.00 × 10^−4 meter2 at 20°C?
(1) 2.80 × 10^−5 Ω (3) 89.3 Ω
(2) 1.12 × 10^−2 Ω (4) 112 Ω

The resistance of a conductor is directly proportional to the length of the conductor and inversely proportional to the area of the conductor. The formula for the resistance is given by

[tex]R = \rho \frac{l}{a}[/tex]

Where, ρ is the resistivity of tungsten, l be the length of tungsten and a be the area of cross section.

The value of resistivity for tungsten is 5.6 x 10^-8 ohm metre.

[tex]R = 5.6\times 10^{-8} \times \frac{20}{10^{-4}}[/tex]

[tex]R = 1.12 \times 10^{-2} Ohm[/tex]

Poojatomarb76id Poojatomarb76id · Answer 2

The resistance of a 20.0-meter-long tungsten rod will be 1.12 ×10⁻² ohm.

What is resistance?

Resistance is a type of opposition force due to which the flow of current is reduced in the material or wire. Resistance is the enemy of the flow of current.

The given date in the problem is;

R is the resistance=?

L is the length = 20.0 m

A is the area= of 1.00 ×10⁻⁴

The resistance to the given condition is found by;

[tex]\rm R= \frac{\rho L}{A} \\\\ \rm R= \frac{5.6 \times 10^-8 \times 20 }{1.0\times 10^{-4}} \\\\\rm R=1.12 \times 10^{-2} \ Ohm[/tex]

Hence the resistance of a 20.0-meter-long tungsten rod will be 1.12 ×10⁻² ohm.

To learn more about the resistance refer to the link;

https://brainly.com/question/20708652