What is the resistance of a cable that is 8000ft long and 1/2in. in diameter?

Question

The electrical resistance(r) of a cable varies directly as its length (l) and inversely as teh square of its diameter(d). If a cable 16,000ft long and 1/4in. in diameter has a resistance of 3.2 ohms, what is the resistance of a cable that is 8000 ft long and 1/2in in diameter?

Answer 1

Resistance is inversely proportional to area of cross section of wire.

So for the 1/2 inch wire, the cross sectional area is:

(1/2 / 1/4)^2 that of the 1/4 inch one = 4 times.

The resistance of 16000 ft of the 1/2 wire should be: 3.2 / 4
= 0.8

But it is 8000 ft we want not 16000. (half the length)

Resistance is proportional to distance. So the resistance should be : 0.8 / 2 = 0.4 ohms

Answer 2

they are not each and every of a similar! confirm that's a right now via cable. Crossovers purely artwork between like gadgets or vehicle sensing gadgets. ok. The cable connection your telephone jack to the dsl modem has RJ-11 jacks on the tip of it. The cable between the modem and your comuter is a right now by way of ethernet cable with RJ-40 5 end. to your desires you will maximum possibly want a Cat 5e or Cat 6 catagory cable. The 802.3 Standar for ethernet cabling specifies a maximum distace of one hundred meters or 328 ft, in case you excede this length sign attenuation and propigation delays develop right into a danger to preformace. So the shor aswer is a Cat 5e or Cat 6, right now-via, RJ45 Ethernet cable is what you're able to be able to desire to make greater the area fom your modem to your computing device.

Answer 3

You need to know whether the conductor is copper or aluminum.

The equation is K x 2i x Length / CM

K for copper (cu) = 12

K for aluminum (al) = 18

CM = circular mils

I = the amount of current that will be travelling on the cable

This will you give you the voltage drop over the length of the cable, which you can then plug into the standard equation:

V = I x R

where V = voltage, I=current, and R = resistance.

simply flip it around V / I = R, fill in the current and voltage and voila.

Answer 4

I get 0.4 Ohms

calculate the resistivity of the material:

3.2 = resistivity * (16000 / (pi * 0.125^2))
resistivity = 9.817 * 10^-6

Then use that to calculate the new resistance

R = 9.817*10 ^-6 * (8000 / (pi * 0.25^2))

.

Answer 5

{[4(diameter)(length)] [ 1+(temp-20)(.0039)} / (pi)(diameter**2)

answer in ohms. all measurements in inches. diameter**2 = diameter squared. .0039 is the coefficient of resistance "per degrees C"

Answer 6

1.6/2 ohms=.8ohms