Practice question

Given: A nichrome wire has a resistance of 100 Ω at 30° C and α = 1.7 × 10⁻⁴°C^{-1 . What is its resistance at 150° C ? These values define the system as per NCERT data. Formula: Use: R_t = R_0 [1 + α (T - T_0)]. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substitute: R_t = 100 [1 + 1.7 × 10⁻⁴(150 - 30)] . Calculate: R_t = 100 [1 + 1.7 × 10⁻⁴ × 120] = 100 [1 + 0.0204] = 102.04 Ω . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.