Q 12-03-103JEE MainJEE Main 2024 (30 Jan, Shift 1)Medium
An electric toaster has resistance of $60\ \Omega$ at room temperature ($27^\circ\text{C}$). The toaster is connected to a $220\ \text{V}$ supply. If the current flowing through it reaches $2.75\ \text{A}$, the temperature attained by the toaster is around: (if $\alpha = 2\times10^{-4}\ {}^\circ\text{C}^{-1}$)
Answer: (C) $1694^\circ\text{C}$
Hot resistance: $R = \dfrac{220}{2.75} = 80\ \Omega$.
$$80 = 60\,[1 + 2\times10^{-4}(T - 27)] \Rightarrow T - 27 = \frac{1/3}{2\times10^{-4}} \approx 1667$$
$$T \approx 1694^\circ\text{C}$$
Solution by Sreeraj P, M.Sc Physics