Three metal rods made of copper, brass, and s | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) Let the temperature of the junction be $T$. The rate of heat flow is given by $H = \frac{KA(T_1 - T_2)}{L}$.Since the rods are joined at a junctio

Vedclass · Accepted Answer

$4.8$

Vedclass · Answer

(C) Let the temperature of the junction be $T$. The rate of heat flow is given by $H = \frac{KA(T_1 - T_2)}{L}$.Since the rods are joined at a junction, the sum of heat currents flowing away from the junction must be zero: $H_{Cu} + H_{Br} + H_{St} = 0$.Given: $A = 4 \,cm^2$ for all rods.$H_{Cu} = \frac{0.92 	imes 4 	imes (T - 100)}{46} = 0.08(T - 100)$$H_{Br} = \frac{0.26 	imes 4 	imes (T - 0)}{13} = 0.08T$$H_{St} = \frac{0.12 	imes 4 	imes (T - 0)}{12} = 0.04T$Summing these: $0.08(T - 100) + 0.08T + 0.04T = 0$$0.08T - 8 + 0.08T + 0.04T = 0$$0.20T = 8 \implies T = 40 \,^{\circ}C$.The rate of heat flow through the copper rod is $H_{Cu} = 0.08(40 - 100) = 0.08(-60) = -4.8 \,cal \,s^{-1}$.The magnitude of the rate of heat flow is $4.8 \,cal \,s^{-1}$.

Similar Questions

Two different rods $A$ and $B$ are kept as shown in the figure. The ratio of thermal conductivities of $A$ and $B$ is

Steam at $373 K$ is passed through a tube of radius $10 cm$ and length $2 m$. The thickness of the tube is $5 mm$ and the thermal conductivity of its material is $390 W m^{-1} K^{-1}$. Calculate the heat lost per second. The outside temperature is $0^{\circ}C$.

The two ends of a rod of length $L$ and a uniform cross-sectional area $A$ are kept at two temperatures $T_1$ and $T_2$ $(T_1 > T_2)$. The rate of heat transfer,$\frac{dQ}{dt}$,through the rod in a steady state is given by:

$A$ $5 \ cm$ thick ice block is present on the surface of water in a lake. The temperature of the air is $-10^{\circ}C$. How much time will it take to double the thickness of the block? (Given: $L = 80 \ cal/g$,$K_{ice} = 0.004 \ cal/s \cdot cm \cdot ^{\circ}C$,$\rho_{ice} = 0.92 \ g/cm^3$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module