Question

The electrons of Rutherford's model of the atom are expected to lose energy because they (1) are attracted by the nucleus (2) strike each other (3) are accelerated (4) are in motion

Short answer

The electrons lose energy because they are accelerated.

Step-by-step solution

- Understand the Problem

The problem asks why electrons in Rutherford's model of the atom are expected to lose energy. Consider the behavior of electrons and the principles of physics that apply to them.

- Analyze Each Option

Evaluate each given option: electrons are attracted by the nucleus, strike each other, are accelerated, or are in motion. Determine which of these could cause energy loss.

- Examine Electromagnetic Radiation

According to classical physics, when charged particles like electrons are accelerated, they emit electromagnetic radiation, losing energy in the process.

- Identify the Correct Cause

As electrons revolve around the nucleus, they are constantly changing direction, which means they are accelerating. The continuous acceleration causes them to emit radiation and lose energy.

- Conclude

Because the continuous acceleration of electrons in Rutherford's model leads them to emit radiation, the correct answer is (3) are accelerated.

Key concepts

electron behavior

In Rutherford's model of the atom, electrons move around the nucleus in circular orbits. This behavior is similar to planets orbiting the sun. However, electrons are not just simple particles; they have unique properties:

• They have a negative charge.
• Their motion is influenced by the positive charge of the nucleus.
• In classical physics, accelerated electrons (those changing speed or direction) emit energy.

This means that as electrons continually move in their orbits, they are always accelerating toward the nucleus. The behavior of electrons in Rutherford's model presents a significant issue: they should be losing energy and spiraling into the nucleus, but this does not actually happen. This conflict between expected behavior and actual observations helped pave the way for further developments in atomic theory.

energy loss

Energy loss in Rutherford's model is tied directly to the motion of electrons. When charged particles like electrons are accelerated, they emit energy in the form of electromagnetic radiation. This emission of energy results in energy loss for the electrons. In a stable orbit, you would expect electrons to constantly lose energy, slow down, and eventually spiral into the nucleus.

• This continuous energy loss is due to the fact that they are being constantly pulled towards the nucleus while moving in an orbit.
• The expected result would be an atom imploding, which contradicts what we observe in reality.

This concept of energy loss due to acceleration presented a major flaw in Rutherford's model and highlighted the need for more refined atomic theories.

electromagnetic radiation

Electromagnetic radiation is a form of energy emitted by accelerating charged particles. When electrons in Rutherford's model are moving around the nucleus, they are accelerating because their direction changes continuously. According to classical physics, this acceleration makes them emit electromagnetic radiation

• This radiation is a form of energy loss.
• It explains why accelerating electrons can't maintain constant energy levels in classical physics.

This phenomenon not only affects atomic models but is also seen in other systems involving accelerating charges. Understanding electromagnetic radiation is crucial for explaining why Rutherford's model couldn't fully describe electron behavior.

classical physics

Classical physics dealt with particles and waves using principles developed before quantum mechanics. According to classical physics, accelerating charges (like electrons in orbit) should emit electromagnetic radiation and lose energy. This was one of the main reasons Rutherford's model had limitations.

• Classical physics couldn't explain the stability of atoms:
• If electrons lost energy as predicted, they would spiral into the nucleus.
• This would make atoms collapse, contradicting everyday experiences and observations.

To solve these contradictions, new theories were needed, such as quantum mechanics, which better described the behavior of electrons on atomic scales. Classical physics’s inability to explain these observations helped push scientific thinking towards more advanced models of the atom.