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neduet
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Homework Statement
A motor winding has a risitance of 80 ohm at room temperature of 20c before
switching on to a 230v. after 4 hour run wionfing resistance is 100 ohm
find the temperature rise if the matrial resistance temperature co-efficient is 1/234.5/c.
R at 20 = 80 ohm
R at t = 100 ohm
alpha =1/234.5
Homework Equations
R at 20/R at t = R at 0c (1 - at)/ R at 0c (1-at)
The Attempt at a Solution
80/100 = 1+0.004264X20/1+0.004264t
t = 83.630 c
Rise is t-20 = 83.630-20
t rise is 63.63 c