The heating element of an electirc toaster is of nichrome. When a vary small current passes through it, at room temperrature `27^@C`, its resistance is `75.3Omega`. When toaster is connected to a 230V supply, the current settles after a few seconds to a steady value of 2.68A. What is the steady temperature of nichrome element? The temperature coefficient of resistance of nichrome over averged temperature range is `1.7xx10^(-4)^(@)C^(-1)`.

The heating element of an electirc toaster is of nichrome. When a vary

1.	The heating element of an electirc toaster is of nichrome. When a vary small current passes through it, at room temperrature `27^@C`, its resistance is `75.3Omega`. When toaster is connected to a 230V supply, the current settles after a few seconds to a steady value of 2.68A. What is the steady temperature of nichrome element? The temperature coefficient of resistance of nichrome over averged temperature range is `1.7xx10^(-4)^(@)C^(-1)`.
Answer» Here, `R_(27) =75.3 Omega`, `alpha=1.7xx10^(-4).^(@)C^(-1),V=230 V, I=2.68A` `R_(t) =230/2.68 =85.82 Omega`, As, `t_(2)-t_(1) =(R_(1)-R_(1))/(R_(1)xxalpha)` `:. t -27 = (R_(1)-R_(27))/(R_(27) xx alpha)=(85.82-75.3)/(75.3xx1.7xx10^(-4))=822^@C` or `t=822 +27 =849^@C`

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