Question

Каким способом-совершением работы или теплопередачей-изменялась внутренняя энергия детали при ее нагревании в печи перед закалкой?При сверлении в ней отверстия?

Answer 1

Внутренняя энергия тела равна:
$E_o=E_k+E_p$
Потенциальная, и кинетическая, оба вида энергии не зависят от температуры, поэтому при нагревании тела,  работа не совершается
При сверлении отверстия работа так же не совершалась.
Работа была бы совершена, если бы тело было поднято на высоту, или двигалось бы с некоторой скоростью

Answer 2

Internal Energy Change During Heating in a Furnace Before Quenching

When a material is heated in a furnace before quenching, the internal energy of the material changes. This change in internal energy is primarily due to the transfer of heat to the material, leading to an increase in its temperature. The internal energy of a material can be altered through various processes, such as heating, which involves the transfer of thermal energy to the material.

Heating Process in a Furnace: - During the heating process in a furnace, the internal energy of the material increases as it absorbs heat from the furnace environment. - The increase in internal energy is primarily in the form of thermal energy, leading to a rise in the material's temperature.

Quenching Process: - After the material is heated in the furnace, it is rapidly cooled through a process known as quenching. This rapid cooling helps to achieve specific material properties, such as increased hardness.

Internal Energy Change During Quenching: - The rapid cooling during quenching causes a decrease in the internal energy of the material, leading to a reduction in its temperature. - This decrease in internal energy is primarily due to the removal of thermal energy from the material as it is rapidly cooled.

Internal Energy Change During Drilling of Holes

When drilling holes in a material, the internal energy of the material can also undergo changes, albeit through a different mechanism.

Drilling Process: - During the drilling process, mechanical work is performed on the material as the drill bit penetrates and removes material to create a hole. - This mechanical work results in a change in the internal energy of the material, primarily in the form of mechanical energy.

Frictional Heating: - The drilling process also generates heat due to friction between the drill bit and the material being drilled. - This frictional heating can lead to an increase in the internal energy of the material, primarily in the form of thermal energy.

Overall Internal Energy Change: - The drilling process results in a complex change in the internal energy of the material, involving both mechanical and thermal energy components.

In summary, the internal energy of a material changes during both the heating process in a furnace before quenching and the drilling of holes, with each process involving different mechanisms for altering the internal energy of the material.