Home
Class 11
PHYSICS
A brick weighing 4.0 kg is dropped into ...

A brick weighing `4.0 kg `is dropped into a `1.0m` deep river from a height of `2.0m` Assuming that `80%` of the gravitational potential energy is finally converted into thermal energy, find this thermal energy in calorie.

Text Solution

Verified by Experts

The correct Answer is:
A, B, C
Total P.E. `= 4 xx 10 xx 3 = 120J`
Energyutilized `= 120 xx (80)/(100)= 96J`
`= (96)/(4.2) = 22.857 cal`
`23 cal`
Promotional Banner

Topper's Solved these Questions

  • CALORIMETRY

    HC VERMA|Exercise Objetive - II|6 Videos

  • CENTRE OF MASS, LINEAR MOMENTUM, COLLISION

    HC VERMA|Exercise Exercises|64 Videos

Similar Questions

Explore conceptually related problems

A ball is dropped on a floor from a height of 2.0m After the collision it rises up to a height of 1.5m . Assume that 40% of the mechanical energy lost goes as thermal energy into the ball. Calculate the rise in the temperature of the ball in the collision specific heat capacity of the ball is 800J kg^(-1) K^(-1)

A 10 kg ball is dropped from a height of 10m. Find (a) the initial potential energy of the ball. (b) the kinetic energy just before it reaches the ground, and (c ) the speed just before it reaches the ground.

Water falling from a 50 m high fall is to be used for generating electric enegy. If 1.8xx10^5kg of water falls per hour and half the gravitational potential energyh can be converted into electric energy, how many 100 W lamps can be it?

A van of mass 1500kg travelling at a speed of 15 m/s is stopped in 10 s Assuming that all the mechanical energy lost appears as thermal energy in the brakes find the average rate of production of thermal energy in cal s^(-1)

Show that for a particle executing simple harmonic motion a. the average value of kinetic energy is equal to the average value of potential energy. b. average potential energy = average kinetic energy =1/2 (total energy) (Hint : average kinetic energy = =1/Tint_(0)^(T) (Kinetic energy) dt and average Potential energy = =1/Tint_(0)^(T) (potential energy) dt

A charge of 2xx10^(4)C flows through an electric heater. The amount of electrical energy converted into thermal energy is 5 MJ. Compute the potential difference across the ends of the heater.

A block of 2 kg is lifted up through 2m from the ground. Calculate the potential energy of the block at that point.

Two small bodies of masses 2.00 kg and 4.00 kg are kept at rest at a separation of 2.0 m. Where should a particle of mass 0.10 kg be placed to experience no net gravitational force from these bodies? The particle is placed at this point. What is the gravitational potential energy of the system of three particle with usual reference level?

HC VERMA-CALORIMETRY-Exercises
  1. An aluminium vessel of mass 0.5kg contains 0.2kg of water at 20^(@)C A...

    Text Solution

    |

  2. A piece of iron of mass 100g is kept inside a furnace for a long time ...

    Text Solution

    |

  3. The temperature of equal masses of three different liquids A ,B and C ...

    Text Solution

    |

  4. Four 2 cmxx2 cmxx 2cm cubes of ice are taken from a refrigerator and p...

    Text Solution

    |

  5. Indian style of cooling drinking water is to keep it in a pitcher havi...

    Text Solution

    |

  6. A cube of iron (density= 8000kg m^(-1), specific heat capacity = 470g ...

    Text Solution

    |

  7. 1kg ice at 0^(@)C is mixed with 1kg of steam at 100^(@)C. What will be...

    Text Solution

    |

  8. Calculate the time required to heat 20kg of water from 10^(@)C to 35^(...

    Text Solution

    |

  9. The number of molecules in a drop of water (0.0018 ml) at room tempera...

    Text Solution

    |

  10. A bullet of mass 20g enters into a fixed wooden block with a speed of ...

    Text Solution

    |

  11. A 50 kg man is running at a speed of 18 kmh^(-1) If all the kinetic en...

    Text Solution

    |

  12. A brick weighing 4.0 kg is dropped into a 1.0m deep river from a heigh...

    Text Solution

    |

  13. A van of mass 1500kg travelling at a speed of 15 m/s is stopped in 10...

    Text Solution

    |

  14. A block of mass 100g slides on a rough horizontal surface .If the spee...

    Text Solution

    |

  15. A 10kg ball and 20kg ball approach each other with velocities 20ms^(-1...

    Text Solution

    |

  16. A ball is dropped on a floor from a height of 2.0m After the collision...

    Text Solution

    |

  17. A copper cube of mass 200g slides down an a rough inclined plane of in...

    Text Solution

    |

  18. A metal block of density 6000 kg m^(-3) and mass 1.2 kg is suspended t...

    Text Solution

    |