Question

Consider a metal rod that has 10 W of heat conduction between its two ends, which are maintained at temperatures of 200 K and 400 K. If we raise the temperature of the hot end from 400 K to 500 K, what is the new rate of heat conduction along the rod? Group of answer choices

Answer 1

Answer:

heat conduction along the rod ( Q/Δt ):

⇒ Q/Δt = 15 W

Explanation:

heat conduction:

• Q/Δt = k.A.(T1 - T2)......fourier law

∴ Q/Δt : heat trasmitted per unit of time.

∴ k: thermal conductivity

∴ A: contact surface area

∴ T1 - T2: temperature difference between its two ends.

⇒ Q/Δt = 10 W

⇒ T1 = 400K ∧ 500K

⇒ T2 = 200K

∴ 10W = k.A(400K - 200K)

⇒ k.A = 10 W/200K = 0.05 W/K

if T1 = 500K

⇒ Q/Δt = (0.05 W/K)(500K - 200K)

⇒ Q/Δt = (0.05 W/K)(300K)

⇒ Q/Δt = 15 W