Unit 7: Quantum, Atomic, and Nuclear Physics

What is a quantum of electromagnetic energy called?

Photon

What phenomenon illustrates light behaving like a stream of photons?

Photoelectric effect

What are the released electrons in the photoelectric effect known as?

Photoelectrons

What does the equation E = hf represent in relation to photons?

E represents energy, h is Planck's constant, and f is frequency.

What is the threshold frequency required for a metal related to?

It is the frequency below which photoelectrons will not be emitted.

What happens if light intensity is increased according to wave theory?

It was expected to cause electrons to leave the metal surface with greater kinetic energy, which was disproven.

What is the strong nuclear force?

A fundamental force that binds protons and neutrons together to form nuclei.

What is binding energy in nuclear physics?

The energy required to disassemble a nucleus into its constituent nucleons.

What happens during alpha decay?

A nucleus emits an alpha particle, which consists of two protons and two neutrons.

What is created during beta negative (β−) decay?

A neutron transforms into a proton and releases an electron (beta particle) and an electron antineutrino.

What is the concept of wave-particle duality?

Electromagnetic radiation propagates like a wave but exchanges energy like a particle.

What does the term 'time dilation' refer to in relativity?

A discrepancy in the passage of time as measured by two observers, one in motion and one at rest.

What are isotopes?

Nuclei that contain the same number of protons but different numbers of neutrons.

What is the mass defect in nuclear physics?

The difference between the mass of a bound nucleus and the sum of the masses of its constituent nucleons.

What type of nuclear reaction involves the splitting of a nucleus?

Nuclear fission.

What does electron capture achieve in nuclear reactions?

It increases the neutron-to-proton ratio by transforming a proton into a neutron.

What is gamma decay characterized by?

It does not change the identity of the nucleus but allows it to shed energy.

What is beta decay?

Beta decay is a type of radioactive decay in which a beta particle (an electron or positron) is emitted from an atomic nucleus.

What are the two types of beta decay?

The two types of beta decay are beta-minus decay (emission of an electron) and beta-plus decay (emission of a positron).

What is alpha decay?

Alpha decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle, consisting of two protons and two neutrons.

What is gamma decay?

Gamma decay is the release of gamma radiation from a nucleus, which occurs when an excited nucleus releases energy without changing its number of protons or neutrons.

Wavelength vs Temperature equation

wavelength = b/T

b

2.9e-3

If T = 5778 K, find the wavelength

502 nm

Area, temperature and rate of radiation equation

P = AoT⁴

o^_

5.67×10^-8

Energy formula

E = hf

h

6.63e-34

Kinetic energy equation

KE = hf - W_o

Momentum final equation

p = h/wavelength