Robert Millikan

Definition

Robert Andrews Millikan was an American physicist who is best known for his oil drop experiment, which provided the first accurate measurement of the charge of an electron. His work on the photoelectric effect also helped confirm the quantum nature of light and contributed to the development of atomic theory.

5 Must Know Facts For Your Next Test

1. Millikan's oil drop experiment demonstrated that electric charge is quantized, meaning it comes in discrete units rather than a continuous spectrum.
2. The results of the oil drop experiment provided the first accurate measurement of the charge of an electron, which is a fundamental constant of nature.
3. Millikan's work on the photoelectric effect, building on the ideas of Max Planck and Albert Einstein, helped confirm the quantum nature of light.
4. Millikan's contributions to atomic theory and the understanding of the electron's properties were crucial to the development of modern physics.
5. Millikan was awarded the Nobel Prize in Physics in 1923 for his work on the photoelectric effect and the determination of the electronic charge.

Review Questions

• Explain the significance of Millikan's oil drop experiment and how it contributed to the evolution of atomic theory.
  • Millikan's oil drop experiment was a landmark study that provided the first accurate measurement of the charge of an electron, a fundamental constant of nature. By suspending charged oil droplets in an electric field and observing their motion, Millikan was able to demonstrate that electric charge is quantized, meaning it comes in discrete units rather than a continuous spectrum. This finding was a crucial step in the development of atomic theory, as it helped confirm the existence of the electron as a discrete subatomic particle and laid the groundwork for a better understanding of atomic structure and behavior.
• Describe how Millikan's work on the photoelectric effect contributed to the quantum theory of light.
  • In addition to his oil drop experiment, Millikan's research on the photoelectric effect also made significant contributions to the evolution of atomic theory. By building on the ideas of Max Planck and Albert Einstein, Millikan's work on the photoelectric effect helped confirm the quantum nature of light, demonstrating that light is composed of discrete packets of energy called photons. This finding was a crucial step in the development of quantum mechanics and the understanding of the wave-particle duality of light, which was essential for the advancement of atomic theory and modern physics.
• Evaluate the overall impact of Millikan's scientific contributions on the field of atomic theory and the broader development of modern physics.
  • Robert Millikan's groundbreaking work on the oil drop experiment and the photoelectric effect had a profound and lasting impact on the evolution of atomic theory and the development of modern physics. By providing the first accurate measurement of the electron's charge and confirming the quantum nature of light, Millikan's research helped establish the fundamental building blocks of the atom and laid the foundation for a deeper understanding of atomic structure and behavior. His contributions were essential for the advancement of quantum mechanics and the emergence of modern physics, which have transformed our understanding of the physical world and enabled countless technological innovations. Millikan's scientific achievements were recognized with the Nobel Prize in Physics, underscoring the significance of his work and its enduring influence on the field of atomic theory and beyond.

Related terms

Oil Drop Experiment: An experiment conducted by Millikan to measure the charge of an electron by suspending charged oil droplets in an electric field and observing their motion.

Photoelectric Effect: The phenomenon where electrons are emitted from a metal surface when light shines on it, which helped confirm the quantum nature of light.

Atomic Theory: The scientific model that describes the structure and behavior of atoms, which Millikan's work helped to develop and refine.