**Question 1:**

### What is a photon?

Explanation: The correct answer is B) A particle of light. A photon is a particle of light that carries energy. It is the smallest discrete unit of electromagnetic radiation and exhibits both particle-like and wave-like properties.

**Question 2:**

### What is the energy of a photon directly proportional to?

Explanation: The correct answer is A) Its frequency. The energy of a photon is directly proportional to its frequency. This relationship is described by the equation E = hf, where E represents the energy, h is Planck's constant, and f is the frequency of the photon.

**Question 3:**

### What is the momentum of a photon proportional to?

Explanation: The correct answer is A) Its wavelength. The momentum of a photon is proportional to its wavelength. This relationship is described by the equation p = h/λ, where p represents the momentum, h is Planck's constant, and λ is the wavelength of the photon.

**Question 4:**

### What is the dual nature of light?

Explanation: The correct answer is D) Its wave-particle duality. The dual nature of light refers to its ability to exhibit both wave-like and particle-like properties. It canbe described as both a wave and a stream of particles (photons) depending on the phenomenon being observed.

**Question 5:**

### Which experiment demonstrated the particle properties of light?

Explanation: The correct answer is B) Photoelectric effect. The photoelectric effect experiment demonstrated the particle properties of light. It showed that light can interact with matter as individual particles (photons) and that the energy of the photons determines the emission of electrons from the material.

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