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An electric toaster has resistance of 60 at room temperature (27 ). The toaster is connected to a 220 V supply. If the current flowing through it reaches 2.75 A, the temperature attained by toaster is around : ( if =2 10-4/ )
(4) 1694
Hot resistance: R= VI= 2202.75=80
R=R0 [1+ (T-27 ) ]
80=60 [1+2 10-4 (T-27 ) ]
T-27= 1/32 10-4 1667
T 1694
Answer: (4)
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