146568 Two rods one made of copper and other made of steel of the same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are $385 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-}$ ${ }^{1} \mathrm{~m}^{-1}$ and $50 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-1} \mathrm{~m}^{-1}$ respectively. The free ends of copper and steel are held at $100^{\circ} \mathrm{C}$ and $0^{\circ} \mathrm{C}$ respectively. The temperature at the junction is, nearly:

146569 Which of the following circular rods, (given radius $r$ and length $l$ ) each made of the same material and whose ends are maintained at the same temperature will conduct most heat:

146570 At what temperature a gold ring of diameter $6.230 \mathrm{~cm}$ be heated so that it can be fitted on a wooden bangle of diameter $6.241 \mathrm{~cm}$ ? Both the diameters have been measured at room temperature $\left(27^{\circ} \mathrm{C}\right)$.
(Given: coefficient of linear thermal expansion of gold $\alpha_{L}=1.4 \times 10^{-5} \mathrm{~K}^{-1}$ )

146571 The steel petrol tank of a car is filled with 30 liters of petrol at $10{ }^{\circ} \mathrm{C}$. if $\alpha_{\text {steel }}$ is $24 \times 10^{-6} /{ }^{\circ} \mathrm{C}$ and $\gamma_{\text {petrol }}$ is $9.9 \times 10^{-4} /{ }^{\circ} \mathrm{C}$, the overflow of petrol at $40{ }^{\circ} \mathrm{C}$ is

146572 A steel wire is suspended vertically from a rigid support. When the wire is loaded with a weight in air, it extended by $X_{a}$. When the weight is completely inside the water, the extension becomes $X_{w}$. The relative density of the material of the weight is

146568 Two rods one made of copper and other made of steel of the same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are $385 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-}$ ${ }^{1} \mathrm{~m}^{-1}$ and $50 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-1} \mathrm{~m}^{-1}$ respectively. The free ends of copper and steel are held at $100^{\circ} \mathrm{C}$ and $0^{\circ} \mathrm{C}$ respectively. The temperature at the junction is, nearly:

146569 Which of the following circular rods, (given radius $r$ and length $l$ ) each made of the same material and whose ends are maintained at the same temperature will conduct most heat:

146570 At what temperature a gold ring of diameter $6.230 \mathrm{~cm}$ be heated so that it can be fitted on a wooden bangle of diameter $6.241 \mathrm{~cm}$ ? Both the diameters have been measured at room temperature $\left(27^{\circ} \mathrm{C}\right)$.
(Given: coefficient of linear thermal expansion of gold $\alpha_{L}=1.4 \times 10^{-5} \mathrm{~K}^{-1}$ )

146571 The steel petrol tank of a car is filled with 30 liters of petrol at $10{ }^{\circ} \mathrm{C}$. if $\alpha_{\text {steel }}$ is $24 \times 10^{-6} /{ }^{\circ} \mathrm{C}$ and $\gamma_{\text {petrol }}$ is $9.9 \times 10^{-4} /{ }^{\circ} \mathrm{C}$, the overflow of petrol at $40{ }^{\circ} \mathrm{C}$ is

146572 A steel wire is suspended vertically from a rigid support. When the wire is loaded with a weight in air, it extended by $X_{a}$. When the weight is completely inside the water, the extension becomes $X_{w}$. The relative density of the material of the weight is

146568 Two rods one made of copper and other made of steel of the same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are $385 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-}$ ${ }^{1} \mathrm{~m}^{-1}$ and $50 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-1} \mathrm{~m}^{-1}$ respectively. The free ends of copper and steel are held at $100^{\circ} \mathrm{C}$ and $0^{\circ} \mathrm{C}$ respectively. The temperature at the junction is, nearly:

146569 Which of the following circular rods, (given radius $r$ and length $l$ ) each made of the same material and whose ends are maintained at the same temperature will conduct most heat:

146570 At what temperature a gold ring of diameter $6.230 \mathrm{~cm}$ be heated so that it can be fitted on a wooden bangle of diameter $6.241 \mathrm{~cm}$ ? Both the diameters have been measured at room temperature $\left(27^{\circ} \mathrm{C}\right)$.
(Given: coefficient of linear thermal expansion of gold $\alpha_{L}=1.4 \times 10^{-5} \mathrm{~K}^{-1}$ )

146571 The steel petrol tank of a car is filled with 30 liters of petrol at $10{ }^{\circ} \mathrm{C}$. if $\alpha_{\text {steel }}$ is $24 \times 10^{-6} /{ }^{\circ} \mathrm{C}$ and $\gamma_{\text {petrol }}$ is $9.9 \times 10^{-4} /{ }^{\circ} \mathrm{C}$, the overflow of petrol at $40{ }^{\circ} \mathrm{C}$ is

146572 A steel wire is suspended vertically from a rigid support. When the wire is loaded with a weight in air, it extended by $X_{a}$. When the weight is completely inside the water, the extension becomes $X_{w}$. The relative density of the material of the weight is

146568 Two rods one made of copper and other made of steel of the same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are $385 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-}$ ${ }^{1} \mathrm{~m}^{-1}$ and $50 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-1} \mathrm{~m}^{-1}$ respectively. The free ends of copper and steel are held at $100^{\circ} \mathrm{C}$ and $0^{\circ} \mathrm{C}$ respectively. The temperature at the junction is, nearly:

146569 Which of the following circular rods, (given radius $r$ and length $l$ ) each made of the same material and whose ends are maintained at the same temperature will conduct most heat:

146570 At what temperature a gold ring of diameter $6.230 \mathrm{~cm}$ be heated so that it can be fitted on a wooden bangle of diameter $6.241 \mathrm{~cm}$ ? Both the diameters have been measured at room temperature $\left(27^{\circ} \mathrm{C}\right)$.
(Given: coefficient of linear thermal expansion of gold $\alpha_{L}=1.4 \times 10^{-5} \mathrm{~K}^{-1}$ )

146571 The steel petrol tank of a car is filled with 30 liters of petrol at $10{ }^{\circ} \mathrm{C}$. if $\alpha_{\text {steel }}$ is $24 \times 10^{-6} /{ }^{\circ} \mathrm{C}$ and $\gamma_{\text {petrol }}$ is $9.9 \times 10^{-4} /{ }^{\circ} \mathrm{C}$, the overflow of petrol at $40{ }^{\circ} \mathrm{C}$ is

146572 A steel wire is suspended vertically from a rigid support. When the wire is loaded with a weight in air, it extended by $X_{a}$. When the weight is completely inside the water, the extension becomes $X_{w}$. The relative density of the material of the weight is

146568 Two rods one made of copper and other made of steel of the same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are $385 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-}$ ${ }^{1} \mathrm{~m}^{-1}$ and $50 \mathrm{~J} \mathrm{~s}^{-1} \mathrm{~K}^{-1} \mathrm{~m}^{-1}$ respectively. The free ends of copper and steel are held at $100^{\circ} \mathrm{C}$ and $0^{\circ} \mathrm{C}$ respectively. The temperature at the junction is, nearly:

146569 Which of the following circular rods, (given radius $r$ and length $l$ ) each made of the same material and whose ends are maintained at the same temperature will conduct most heat:

146570 At what temperature a gold ring of diameter $6.230 \mathrm{~cm}$ be heated so that it can be fitted on a wooden bangle of diameter $6.241 \mathrm{~cm}$ ? Both the diameters have been measured at room temperature $\left(27^{\circ} \mathrm{C}\right)$.
(Given: coefficient of linear thermal expansion of gold $\alpha_{L}=1.4 \times 10^{-5} \mathrm{~K}^{-1}$ )

146571 The steel petrol tank of a car is filled with 30 liters of petrol at $10{ }^{\circ} \mathrm{C}$. if $\alpha_{\text {steel }}$ is $24 \times 10^{-6} /{ }^{\circ} \mathrm{C}$ and $\gamma_{\text {petrol }}$ is $9.9 \times 10^{-4} /{ }^{\circ} \mathrm{C}$, the overflow of petrol at $40{ }^{\circ} \mathrm{C}$ is

146572 A steel wire is suspended vertically from a rigid support. When the wire is loaded with a weight in air, it extended by $X_{a}$. When the weight is completely inside the water, the extension becomes $X_{w}$. The relative density of the material of the weight is