A copper coil has a resistance of 200 ohm when its mean temperature is...
The temperature coefficient of copper is 0.00428 centigrade-1
R1=R0(1+temp. coeff.*T1)= 200(1+0.00428*80)= 268.5 ohm.
View all questions of this testA copper coil has a resistance of 200 ohm when its mean temperature is...
Given:
Resistance of copper coil at 0 degree Celsius (T1) = 200 ohm
Mean temperature of copper coil (T2) = 80 degree Celsius
We need to find the resistance of the coil at T2.
Formula:
The resistance of a conductor (in this case, copper coil) changes with temperature. The change in resistance can be calculated using the following formula:
R2 = R1 [1 + α (T2 - T1)]
Where,
R1 = initial resistance (at temperature T1)
R2 = final resistance (at temperature T2)
α = temperature coefficient of resistance (for copper, α = 0.00404/degree Celsius)
T1 = initial temperature
T2 = final temperature
Calculation:
Substituting the given values in the formula, we get:
R2 = 200 [1 + (0.00404 x (80-0))]
R2 = 200 [1 + (0.00404 x 80)]
R2 = 200 [1 + 0.3232]
R2 = 200 x 1.3232
R2 = 268.64 ohm
Rounding off the answer to one decimal place, we get:
R2 = 268.6 ohm
Therefore, the correct option is (a) 268.5 ohm.
A copper coil has a resistance of 200 ohm when its mean temperature is...
The temperature coefficient of copper is 0.00428 C-1.
R=Rref[1+alpha (T-Tref) ]
R=200[1+0.00428(80-0) ]=268.5 ohm.