The temperature coefficient of a resistance wire is 0.00125 per degree.

The temperature coefficient of a resistance wire is 0.00125 per degree. The resistance at 300 K is 1 Ω. At what temperature its resistance will be 2Ω?

Options

(a) 1154 K
(b) 1127 K
(c) 600 K
(d) 1400 K

Correct Answer:

1127 K

Explanation:

Temperature = 300 K = 300 – 273 = 27°C

R₂₇ = R₀ (1 + 27 α) ⇒ 1 = R₀ (1 + 27 α)

Rt = R₀ (1 + αt) ⇒ 2 = R₀ (1 + αt)

2 / 1 = (1 + αt) / (1 + 27 α) ⇒ 1 + αt = 2 + 54α

⇒ αt = 1 +| 54 α ⇒ 0.00125t = 1 + 54 × 0.00125

⇒ t = 854°C = 854 + 273 = 1127 K

admin:

Related Questions

  1. A common emitter amplifier has a voltage gain of 50, an input impedance of 100Ω
  2. Reactance of a capacitor of capacitance C µF for A.C freqency (400 / π) Hz is 25 ohm
  3. Point masses m₁ and m₂ are placed at the opposite ends of a rigid rod of length L,
  4. When the disc rotates with uniform angulr velocity.Which of the following is not true?
  5. The wave described by y = 0.25 sin (10 2πx – 2πt), where x and y are in meters