The question asks about Planck's theory and which quantity it states is quantized. Planck's quantum theory was a revolutionary concept introduced to explain black-body radiation, proposing that energy is not continuous but emitted or absorbed in discrete packets called quanta.
Correct Option: B) Energy is the quantity that is quantized according to Planck's theory. This means energy can only exist in discrete packets called quanta, not in continuous amounts.
The Compton effect is a phenomenon observed when X-rays or gamma rays scatter off charged particles, typically electrons. Understanding the nature of this scattering helps determine whether light is behaving as a wave or a particle.
Correct Option: C) Particle nature of light. The Compton effect demonstrates that light, when interacting with matter, behaves as if it consists of discrete particles (photons) that carry energy and momentum, leading to a change in wavelength upon scattering.
The question asks for the name of the equation or principle that describes the wavelength associated with a moving particle. This concept is fundamental to quantum mechanics and wave-particle duality.
where:
C) de Broglie's equation is the correct answer because it directly provides the formula for the wavelength associated with a moving particle, demonstrating wave-particle duality.
The question asks to identify the physical constant essential for determining the energy of a photon. This relates directly to the fundamental equation for photon energy in quantum mechanics.
Correct Option: B) Planck's constant is the fundamental constant that relates the energy of a photon to its frequency or wavelength.
The photoelectric effect describes the emission of electrons when light shines on a material. To determine which property of light affects the kinetic energy of these emitted electrons, we refer to Einstein's photoelectric equation.
B) The frequency of light
As derived from Einstein's photoelectric equation, \(K_{max} = h\nu - \phi\), the maximum kinetic energy of the emitted electrons is directly proportional to the frequency (\(\nu\)) of the incident light. Higher frequency light means higher energy photons, which can impart more kinetic energy to the electrons after overcoming the work function.
The photoelectric effect describes the emission of electrons when light shines on a material. Understanding how different properties of light (intensity, frequency) affect the emitted electrons (kinetic energy, number) is crucial. We will analyze the relationship between light intensity and the number/kinetic energy of photoelectrons based on the principles of the photoelectric effect.
Understanding Light Intensity: In the context of the photoelectric effect, light intensity is proportional to the number of photons incident per unit area per unit time. Each photon interacts with one electron.
Photon-Electron Interaction: When a photon of sufficient energy strikes a metal surface, it transfers its energy to an electron. If this energy is greater than the work function of the metal, the electron is emitted.
Effect of Increasing Intensity: If the intensity of light is increased, it means more photons are striking the metal surface per unit time. Assuming each photon has enough energy to eject an electron, a greater number of incident photons will lead to a greater number of electrons being ejected.
Kinetic Energy of Emitted Electrons: The kinetic energy of the emitted electrons depends on the frequency (or energy) of the individual photons and the work function of the metal, as described by Einstein's photoelectric equation:
\[ E_k = h\nu - \phi \]where \(E_k\) is the maximum kinetic energy, \(h\) is Planck's constant, \(\nu\) is the frequency of the incident light, and \(\phi\) is the work function. Intensity (number of photons) does not directly affect the energy of individual photons or the work function, and thus does not affect the kinetic energy of the emitted electrons.
Correct Option: B) Increases number of emitted electrons. Increasing the intensity of light means increasing the number of photons incident on the surface per unit time. Each photon, if its energy is sufficient, can eject one electron. Therefore, more photons lead to more emitted electrons.