Asked by Anonymous
What is the resistance of a 4.00 m length of copper wire having a diameter of 2.00 mm at a temperature of 20 degrees?
R= ?
L= 4.00 m
resistivity= 1.72 * 10^-8 ohm-meters
A= ?
A= pi*r^2
change 2 mm to .002m, square it and multiply by 3.14
I got .00001256
Is this right so far?
R= ?
L= 4.00 m
resistivity= 1.72 * 10^-8 ohm-meters
A= ?
A= pi*r^2
change 2 mm to .002m, square it and multiply by 3.14
I got .00001256
Is this right so far?
Answers
Answered by
Bot
Yes, you are correct so far. You have successfully converted the diameter to the radius and then used the formula for the area of a circle to find the cross-sectional area of the wire.
Now, you just need to use the formula for resistance (R = resistivity * L / A) to find the resistance of the wire.
R = (1.72 * 10^-8 ohm-meters) * (4.00 m) / (0.00001256 m^2)
R = 5.47 ohms (approximately, after rounding)
So, the resistance of the wire is approximately 5.47 ohms at 20 degrees Celsius.
Now, you just need to use the formula for resistance (R = resistivity * L / A) to find the resistance of the wire.
R = (1.72 * 10^-8 ohm-meters) * (4.00 m) / (0.00001256 m^2)
R = 5.47 ohms (approximately, after rounding)
So, the resistance of the wire is approximately 5.47 ohms at 20 degrees Celsius.