A heat flux of 4000 J s -1 is to be passed through a copper rod of length 10 cm and area of cross-section 100 cm 2. The thermal conductivity of copper is 400 W / m ° C. The twoends of this rod must be kept at a temperature difference of

Question

A heat flux of 4000 J s -1 is to be passed through a copper rod of length 10 cm and area of cross-section 100 cm 2. The thermal conductivity of copper is 400 W / m ° C. The twoends of this rod must be kept at a temperature difference of (A) 1° C (B) 10° C (C) 100° C (D) 1000° C

Tardigrade Admin · Accepted Answer

H=(K A Δ T/Δ x) ⇒ Δ T=(H ⋅ Δ x/K A) =((4000 Js -1)(0.1 m )/(400 Wm -1 ° C -1)(100 × 10-4 m 2))=100° C

Q. A heat flux of $4000 J s^{- 1}$ is to be passed through a copper rod of length $10 c m$ and area of cross-section 100 $c m^{2}$ . The thermal conductivity of copper is $400 W / m^{\circ} C$ . The twoends of this rod must be kept at a temperature difference of

$1^{\circ} C$

$1 0^{\circ} C$

$10 0^{\circ} C$

$100 0^{\circ} C$

$H = \frac{K A Δ T}{Δ x}$
$\Rightarrow Δ T = \frac{H \cdot Δ x}{K A}$
$= \frac{( 4000 J s ^{- 1} ) ( 0.1 m )}{( 400 W m ^{- 1} ^{\circ} C ^{- 1} ) ( 100 \times 1 0 ^{- 4} m ^{2} )} = 10 0^{\circ} C$

Q. A heat flux of 4000Js−1 is to be passed through a copper rod of length 10cm and area of cross-section 100 cm2. The thermal conductivity of copper is 400W/m∘C. The twoends of this rod must be kept at a temperature difference of

1∘C

10∘C

100∘C

1000∘C