In which of the situations listed below is energy being transferred as heat to the system in order for the system to do work? In which situation is work being done on the system in order for energy to be transferred from the system as heat?
a. Two sticks are rubbed together to start a fire.
b. A firecracker explodes.
c. A red-hot iron bar is set aside to cool.
2. Identify the following processes as isothermal, isovolumetric, or adiabatic:
a. a tire being rapidly inflated
b. a tire expanding gradually with heating
c. a tire being heated while in a rigid metal container
niga biga since 2010
I want the answer, not a question?
#1 is option a
#2 a is adiabatic
b is isothermal
c is isovolumetric
To determine which situation involves energy being transferred as heat to the system in order for the system to do work, and which situation involves work being done on the system in order for energy to be transferred from the system as heat, we need to understand the basic principles of energy transfer.
1. Two sticks are rubbed together to start a fire.
In this situation, work is being done on the system (the sticks) by external forces (the people rubbing the sticks). The mechanical work done compresses and deforms the sticks, increasing their internal energy. As a result, the system gets hotter, and energy is transferred from the system as heat.
2. A firecracker explodes.
During the explosion, the energy released is in the form of rapidly expanding gases and light. In this case, energy is transferred as heat to the surroundings, but no work is done on or by the system.
3. A red-hot iron bar is set aside to cool.
In this scenario, energy is transferred from the system (the red-hot iron bar) to the surroundings as heat. No work is being done on or by the system.
Now, let's identify the processes mentioned as either isothermal, isovolumetric, or adiabatic:
1. A tire being rapidly inflated.
During rapid inflation, the air pressure inside the tire increases, resulting in an increase in temperature as well. Since the process occurs rapidly and without heat flow into or out of the system, it can be considered adiabatic.
2. A tire expanding gradually with heating.
In this case, the tire expands gradually due to heating. As the volume of the tire remains constant, there is no change in volume (isovolumetric). However, since heat is being added to the system, it cannot be considered adiabatic. Thus, the process is isovolumetric only.
3. A tire being heated while in a rigid metal container.
When a tire is heated while inside a rigid metal container, the volume of the system (tire + air) remains constant as it cannot expand or contract. Since the volume is constant, the process is isovolumetric. Heat is being added to the system, so it is not adiabatic. Therefore, the process is isovolumetric.
By understanding the concepts of work, heat transfer, and the specific conditions of each process, we can determine whether energy is being transferred to or from the system as heat and identify the type of process.