Answer:
The temperature of the windings are 60.61 °C
Explanation:
Step 1: Data given
Resistance = 50 Ω
Temperature = 20.0 °C
After the motor has run for several hours the resistance rises to 58Ω.
Step 2: Calculate the new temperature
Formula: R = Rref(1 + α(T-Tref))
⇒with α = temperature coëfficiënt of Cupper at 20 °C = 0.00394/°C
⇒with Tref = reference temperature = 20°C
⇒with T = end temperature = TO BE DETERMINED
⇒with R = resistance at end temperature = 58Ω
⇒with Rref = resistance at reference temperature = 50 Ω
==> T = (R/Rref - 1)/α + Tref
T = (58/50) - 1 )/ 0.00394 + 20
T = 60.61 °C
The temperature of the windings are 60.61 °C
Answer:
If a material has high thermal conductivity, it is a conductor.
If a material has low thermal conductivity, it is an insulator.
Answer:
A C
Explanation:
The statement of the exercise is a bit strange, but if the distance between the load increases.
The following phenomena must occur.
* If the charge has a spatial distribution, the electric field should reduce the electric field of a point charge at the same distance
* As the distance increases the value of the electric field decreases in quadratic form
therefore when reviewing the correct answers are
if the total load is q, answer A is correct
and answer C is always correc
1st ionizaton energy has a trend from down to up and from left to right. Since Na and Al are on the same period (row), then the we look at which is the the furthest to the right and that would be Al.
Answer:
c = 3.00E108 m/s = 3.00E5 km/s
t = S / v = 3.84E5 / 3.00E5 = 1.28 sec
