Home
Class 11
PHYSICS
A uniform slab of dimension 10cmxx10cmxx...

A uniform slab of dimension `10cmxx10cmxx1cm` is kept between two heat reservoir at temperatures `10^(@)C` and `90^(@)C`. The larger surface areas touch the reservoirs. The thermal conductivity of the material is `0.80Wm^(-1)C^(-1)` . Find the amount of heat flowing through the slab per minute.

Text Solution

AI Generated Solution

The correct Answer is:
To find the amount of heat flowing through the slab per minute, we can use the formula for heat conduction, which is given by Fourier's law: \[ Q = \frac{k \cdot A \cdot \Delta T}{d} \] Where: - \( Q \) = heat transfer per second (in Joules per second or Watts) - \( k \) = thermal conductivity of the material (in W/m°C) - \( A \) = area through which heat is conducted (in m²) - \( \Delta T \) = temperature difference across the slab (in °C) - \( d \) = thickness of the slab (in meters) ### Step 1: Convert dimensions to meters The dimensions of the slab are given as 10 cm x 10 cm x 1 cm. We need to convert these dimensions to meters: - Length = 10 cm = 0.1 m - Width = 10 cm = 0.1 m - Thickness = 1 cm = 0.01 m ### Step 2: Calculate the area (A) The area \( A \) of the larger surface is: \[ A = \text{Length} \times \text{Width} = 0.1 \, \text{m} \times 0.1 \, \text{m} = 0.01 \, \text{m}^2 \] ### Step 3: Determine the temperature difference (\( \Delta T \)) The temperature difference between the two reservoirs is: \[ \Delta T = T_{\text{hot}} - T_{\text{cold}} = 90°C - 10°C = 80°C \] ### Step 4: Use the thermal conductivity (k) The thermal conductivity \( k \) is given as: \[ k = 0.80 \, \text{W/m°C} \] ### Step 5: Use the thickness (d) The thickness \( d \) of the slab is: \[ d = 0.01 \, \text{m} \] ### Step 6: Substitute values into the heat transfer formula Now we can substitute all the values into the formula: \[ Q = \frac{0.80 \, \text{W/m°C} \cdot 0.01 \, \text{m}^2 \cdot 80°C}{0.01 \, \text{m}} \] ### Step 7: Calculate \( Q \) Calculating \( Q \): \[ Q = \frac{0.80 \cdot 0.01 \cdot 80}{0.01} = 0.80 \cdot 80 = 64 \, \text{J/s} \] ### Step 8: Convert to heat flow per minute To find the heat flow per minute, we multiply by 60 seconds: \[ Q_{\text{per minute}} = 64 \, \text{J/s} \times 60 \, \text{s} = 3840 \, \text{J/min} \] ### Final Answer The amount of heat flowing through the slab per minute is: \[ \boxed{3840 \, \text{J/min}} \]

To find the amount of heat flowing through the slab per minute, we can use the formula for heat conduction, which is given by Fourier's law: \[ Q = \frac{k \cdot A \cdot \Delta T}{d} \] Where: - \( Q \) = heat transfer per second (in Joules per second or Watts) ...
Promotional Banner

Topper's Solved these Questions

  • HEAT TRANSFER

    HC VERMA ENGLISH|Exercise QUESTIONS FOR SHORT ANSWER|11 Videos
  • HEAT TRANSFER

    HC VERMA ENGLISH|Exercise OBJECTIVE II|6 Videos
  • HEAT AND TEMPERATURE

    HC VERMA ENGLISH|Exercise Objective 2|6 Videos
  • INTRODUCTION TO PHYSICS

    HC VERMA ENGLISH|Exercise Question for short Answer|4 Videos
HC VERMA ENGLISH-HEAT TRANSFER-EXERCIESE
  1. A uniform slab of dimension 10cmxx10cmxx1cm is kept between two heat r...

    Text Solution

    |

  2. A liquid-nitrogen container is made of a 1-cm thick styrofoam sheet ha...

    Text Solution

    |

  3. The normal body-temperature of a person is 97^(@)F . Calculate the rat...

    Text Solution

    |

  4. Water is boiled in a container having a bottom of surface area 25cm^(2...

    Text Solution

    |

  5. One end of a steel rod (K=46Js^(-1)m^(-1)C^(-1)) of length 1.0m is kep...

    Text Solution

    |

  6. An icebox almost completely filled with ice at 0^(@)C is dipped into a...

    Text Solution

    |

  7. A pitcher with 1-mm thick porous walls contain 10kg of water. ,Water c...

    Text Solution

    |

  8. A steel frame (K=45Wm^(-1)C^(-1)) of total length 60cm and cross secti...

    Text Solution

    |

  9. Water at 50^(@)C is filled in a closed cylindrical vessel of height 10...

    Text Solution

    |

  10. The left end of a copper rod (length=20cm, Area of cross section=0.2cm...

    Text Solution

    |

  11. The ends of a metre stick are maintain at 100^(@)C and 0^(@)C . One en...

    Text Solution

    |

  12. A cubical box of volume 216cm^(3) is made up of 0.1cm thick wood, The ...

    Text Solution

    |

  13. Figure shows water in a container having 2.0-mm thick walls made of a ...

    Text Solution

    |

  14. On a winter day when the atmospheric temperature drops to -10^(@)C , i...

    Text Solution

    |

  15. Consider the situation of the previous problem. Assume that the temper...

    Text Solution

    |

  16. Three rods of lengths 20cm each and area of cross section 1cm^(2) are ...

    Text Solution

    |

  17. A semicircular rods is joined at its end to a straight rod of the same...

    Text Solution

    |

  18. A metal rod of cross sectional area 1.0cm^(2) is being heated at one e...

    Text Solution

    |

  19. Steam at 120^(@)C is continuously passed through a 50-cm long rubber t...

    Text Solution

    |

  20. A hole of radius r(1) is made centrally in a uniform circular disc of ...

    Text Solution

    |