Question

Which of the following processes are spontaneous? a. A house is built. b. A satellite is launched into orbit. c. A satellite falls back to earth. d. The kitchen gets cluttered.

Short answer

The spontaneous processes among the given options are: c. A satellite falls back to Earth. d. The kitchen gets cluttered.

Step-by-step solution

a. A house is built.

Building a house requires work, effort, and planning from humans and machines. It does not occur on its own without any assistance. Therefore, a house being built is not a spontaneous process.

b. A satellite is launched into orbit.

Launching a satellite into orbit requires a tremendous amount of energy and planning. It involves designing and building the satellite, as well as planning and executing the launch. This process does not occur naturally without human intervention. So, the launching of a satellite is not a spontaneous process.

c. A satellite falls back to earth.

Once a satellite is in orbit, it may fall back to Earth due to the gravitational pull of our planet. No external force or assistance is required for a satellite to fall back to Earth; it is a natural process as gravity works over time and slows down the satellite. Thus, a satellite falling back to Earth is a spontaneous process.

d. The kitchen gets cluttered.

Clutter in a kitchen occurs over time as items are used and not put back in their original places. This process of clutter accumulation does not require any additional assistance or force. It is simply the result of natural tendencies and movements in a busy environment. Therefore, the kitchen getting cluttered is a spontaneous process. In conclusion, the spontaneous processes among the given options are: c. A satellite falls back to earth. d. The kitchen gets cluttered.

Key concepts

Thermodynamics

Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, radiation, and physical properties of matter. At the heart of thermodynamics lie four fundamental laws which explain how these physical quantities are related and how they affect matter and its changes of state.

The first law, known as the law of conservation of energy, states that energy cannot be created or destroyed in an isolated system. The second law, which is particularly relevant to the concept of spontaneous processes, asserts that entropy of any isolated system always increases.

A spontaneous process in thermodynamics is a reaction or change that occurs naturally without any external intervention. These processes are characterized by a natural flow from a state of higher energy to lower energy, resulting in an increase in the overall entropy of the system. For example, in the original exercise, the cluttering of a kitchen is a spontaneous process because it leads to an increase in the system's entropy.

Entropy

Entropy is a measure of the disorder or randomness in a system, and it is a key concept in the study of thermodynamics. In general terms, systems will spontaneously move towards a state of higher entropy. This is a way of expressing the second law of thermodynamics, which states that the entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.

In the original exercise, the cluttering of a kitchen is described as a spontaneous process. From the perspective of entropy, this can be understood as the kitchen moving from a more ordered state (everything in its place) to a more disordered state (items scattered randomly), which represents an increase in entropy with no need for external energy to induce this transition.

Gravitational Pull

Gravitational pull refers to the attractive force that exists between any two masses. This fundamental force is what keeps planets in orbit around stars, moons in orbit around planets, and it is the reason why objects fall towards the earth when dropped. In the context of spontaneous processes, gravitational pull can facilitate these without the need for an external force or energy.

For instance, as outlined in the solution to the original exercise, a satellite falling back to Earth illustrates a spontaneous process dictated by gravitational pull. The Earth's gravity exerts a force on the satellite, causing it to lose energy and eventually re-enter the atmosphere. This natural occurrence does not require a deliberate action to initiate, as the gravitational pull is a constant, natural force acting on the satellite.

Natural Occurrence

A natural occurrence is an event that happens without human intervention. It is driven by the forces of nature and the laws of physics governing our universe. In many cases, natural occurrences are spontaneous processes, as they proceed without the need for external energy or force.

In the context of the textbook problem, the cluttering of a kitchen and the falling of a satellite back to Earth are both examples of natural occurrences, despite the former involving human activity. The key aspect that makes them spontaneous is that they are inevitable outcomes based on the inherent tendencies of the system – the kitchen becomes cluttered as part of the natural usage of the space, and the satellite falls back to Earth because of the innate gravitational pull of the planet.