Home
Class 11
PHYSICS
Two insulated metal bars each of length ...


Two insulated metal bars each of length 5 cm and rectangular cross section with sides 2 cm and 3 cm are wedged between two walls, one held at `100^@C` and the other at `0^@C`. The bars are made of lead and silver. `K_(pb)=350 W//mK,K_(Ag)=425W//mK`.
Thermal corrent through lead bar is

A

210 W

B

420 W

C

510 W

D

930 W

Text Solution

Verified by Experts

The correct Answer is:
B
Resistance of lead bar
`R_(pb)=(l_(pb))/(K_(pb)A_(pb))=(5xx10^-2)/(350xx6xx10^-4)`
`=(10)/(21)=(5)/(21)(K)/(W)`
Thermal current through lead bar
`I_(pb)=(DeltaT)/(R_pb))=(100xx21)/(5)=420W`
Promotional Banner

Topper's Solved these Questions

  • CALORIMETRY

    CENGAGE PHYSICS ENGLISH|Exercise Integer|8 Videos

  • CALORIMETRY

    CENGAGE PHYSICS ENGLISH|Exercise Solved Example|13 Videos

  • CALORIMETRY

    CENGAGE PHYSICS ENGLISH|Exercise Multiple Correct|25 Videos

  • BASIC MATHEMATICS

    CENGAGE PHYSICS ENGLISH|Exercise Exercise 2.6|20 Videos

  • CENTRE OF MASS

    CENGAGE PHYSICS ENGLISH|Exercise INTEGER_TYPE|1 Videos

Similar Questions

Explore conceptually related problems

Two insulated metal bars each of length 5 cm and rectangular cross section with sides 2 cm and 3 cm are wedged between two walls, one held at 100^@C and the other at 0^@C . The bars are made of lead and silver. K_(pb)=350 W//mK,K_(Ag)=425 W//mK . Total thermal current through the two bar system is

Two insulated metal bars each of length 5 cm and rectangular cross section with sides 2 cm and 3 cm are wedged between two walls, one held at 100^@C and the other at 0^@C . The bars are made of lead and silver. K_(pb)=350 W//mK,K_(Ag)=425 W//mK . Equevalent thermal resistence of the two bar system is

A copper rod of length 75 cm and an iron rod of length 125cm are joined together end to end . Both are of circular cross section with diameter 2 cm . The free ends of the copper and iron are maintained at 100^@C and 0^@C respectively . The surface of the bars are insulated thermally . The temperature of the copper -iron junction is [Thermal conductivity of the copper is 386.4 W//m-K and that of iron is 48.46W//m-K ].

A bar of copper of length 75cm and a bar of steel of length 125cm are joined together end to end. Both are of circular cross section with diameter 2cm . The free ends of the copper and the steel bars are maintained at 100^(@)C and 0^(@)C respectively. The curved surface of the bars are thermally insulated. What is the temperature of the copper-steel junction? What is the amount of heat transmitted per unit time across the junction? Thermal conductivity of copper is 386Js^(-1)m^(-1) C^(-1) and that of steel is 46Js^(-1)m^(-1) C^(-1)

Two smooth sphere each of radius 5cm and weight W rest one on the other inside a fixed smooth cylinder of radius 8cm. The reaction between the sphere and the vertical side of the cylinder are:

Two smooth sphere each of radius 5cm and weight W rest one on the other inside a fixed smooth cylinder of radius 8cm. The reaction between the sphere and the vertical side of the cylinder are:

A copper rod 2 m long has a circular cross-section of radius 1 cm. One end is kept at 100^@C and the other at 0^@C . The surface is insulated so that negligible heat is lost through the surface. In steady state, find (a) the thermal resistance of the bar (b) the thermal current H (c) the temperature gradient (dT)/(dx) and (d) the temperature at a distance 25 cm from the hot end. Thermal conductivity of copper is 401 W//m.K.

A copper rod 2 m long has a circular cross-section of radius 1 cm. One end is kept at 100^@C and the other at 0^@C . The surface is insulated so that negligible heat is lost through the surface. In steady state, find (a) the thermal resistance of the bar (b) the thermal current H (c) the temperature gradient (dT)/(dx) and (d) the temperature at a distance 25 cm from the hot end. Thermal conductivity of copper is 401 W//m-K.

The ends of copper rod of length 1m and area of cross section 1cm^(2) are maintained at 0^(@)C and 100^(@)C . At the centre of rod, there is a source of heat of 32W . The thermal conductivity of copper is 400W//mK

Figure shows a steel rod joined to a brass rod. Each of the rods has length of 31 cm and area of cross-section 0.20 cm^(2) . The junction is maintained at a constant temperature 50^(@)C and the two ends are maintained at 100^(@)C . The amount of heat taken out from the cold junction in 10 minutes after the steady state is reached in n xx 10^(2)J . Find 'n' the thermal conductivities are K_(steel) = 46 W//m-^(@)C and K_(brass) = 109 W//m-^(@)C .

CENGAGE PHYSICS ENGLISH-CALORIMETRY-Comprehension
  1. Assume that the thermal conductivity of copper is twice that of alumin...

    Text Solution

    |

  2. Assume that the thermal conductivity of copper is twice that of alumin...

    Text Solution

    |

  3. A thin copper rod of uniform cross section A square metres and of leng...

    Text Solution

    |

  4. A thin copper rod of uniform cross section A square metres and of leng...

    Text Solution

    |

  5. A thin copper rod of uniform cross section A square metres and of leng...

    Text Solution

    |

  6. An immersion heater, in an insulated vessel of negligible heat capacit...

    Text Solution

    |

  7. An immersion heater, in an insulated vessel of negligible heat capacit...

    Text Solution

    |

  8. An immersion heater, in an insulated vessel of negligible heat capacit...

    Text Solution

    |

  9. A body of area 0.8xx10^-2m^2 and mass 5xx10^-4kg directly faces the su...

    Text Solution

    |

  10. A body of area 0.8xx10^(-2) m^(2) and mass 5xx10^(-4) kg directly face...

    Text Solution

    |

  11. A body of area 0.8xx10^-2m^2 and mass 5xx10^-4kg directly faces the su...

    Text Solution

    |

  12. A copper collar is to fit tightly about a steel shaft that has a diame...

    Text Solution

    |

  13. A copper collar is to fit tightly about a steel shaft that has a diame...

    Text Solution

    |

  14. A copper collar is to fit tightly about a steel shaft that has a diame...

    Text Solution

    |

  15. Two insulated metal bars each of length 5 cm and rectangular cross sec...

    Text Solution

    |

  16. Two insulated metal bars each of length 5 cm and rectangular cross sec...

    Text Solution

    |

  17. Two insulated metal bars each of length 5 cm and rectangular cross sec...

    Text Solution

    |

  18. A 0.60 kg sample of water and a sample of ice are placed in two compar...

    Text Solution

    |

  19. A 0.60 kg sample of water and a sample of ice are placed in two compar...

    Text Solution

    |

  20. A 0.60 kg sample of water and a sample of ice are placed in two compar...

    Text Solution

    |