Can you look up the resisitivity of nichrome?
Resistance= resitivity*deltaLength/area
The resistance should be determined by the power and voltage....R=V^2 /power
A piece of Nichrome wire has a radius of 8.0 10-4 m. It is used in a laboratory to make a heater that dissipates 2.00 102 W of power when connected to a voltage source of 120 V. Ignoring the effect of temperature on resistance, estimate the necessary length of wire.
3 answers
Please tell me where I went wrong.
R= V^2/power
R= 120V^2/2.00x10^2
R= 72
Resistance = restivity x delta Length/ area
72 = (100x10^-8)(delta length/ pi r^2)
72 = 9100x10^-8) (delta length/ 0.000002011)
72 - (100x10^-8)*(0.000002011) = deltaL
0.000144792 = delta Length
R= V^2/power
R= 120V^2/2.00x10^2
R= 72
Resistance = restivity x delta Length/ area
72 = (100x10^-8)(delta length/ pi r^2)
72 = 9100x10^-8) (delta length/ 0.000002011)
72 - (100x10^-8)*(0.000002011) = deltaL
0.000144792 = delta Length
72 * PI * (8E-4^2) * (1 / 9 100E-8) = 1.59 metes
1 answer