Unit 7 & 12

Question 1

Lyman series

Answer 1

UV, transition to n=1

Question 2

Balmer series

Answer 2

Visible, transition to n=2

Question 3

Paschen series

Answer 3

IR, transition to n=3

Question 4

Isotope

Answer 4

A version of an atom with the same number of protons but different number of neutrons

Question 5

Absorption of alpha particle

Answer 5

Skin, paper, 5cm air

Question 6

Absorption of beta

Answer 6

A few cms body tissue, a few mms metal , 25fm air

Question 7

Absorption of gamma

Answer 7

A few cms lead, several ms concrete

Question 8

Half-life

Answer 8

The time taken for half of the initial number of nuclei to decay OR for the activity to fall by half

Question 9

The unified atomic mass unit

Answer 9

1/12th the rest mass of an unbound C12 atom in its nuclear and electronic ground state.

Question 10

Nuclear binding energy

Answer 10

The energy required to completely separate the nucleons in an atom.

Question 11

Mass defect

Answer 11

The difference in mass of the products and reactants of a nuclear reaction.

Question 12

Hadron

Answer 12

A particle formed from quarks.

Question 13

Baryon

Answer 13

A particle formed from 3 quarks.

Question 14

Meson

Answer 14

A particle formed from 2 quarks.

Question 15

Lepton

Answer 15

Particle from electron and neutrino family.

Question 16

Boson

Answer 16

Force carrying particle.

Question 17

The Photoelectric effect - Work Function

Answer 17

The minimum quantity of energy that is required to remove an electron to infinity from the surface of a given solid, usually a metal.

Question 18

Decay Constant

Answer 18

the probability that an individual nucleus will decay in a given time interval.

Question 19

Activity of Sample

Answer 19

the number of nuclei decaying in a second (Bq).

Question 20

Quantization

Answer 20

Conversion of a continuous range (spectrum) of values into a finite range of discrete values.

Question 21

Photon

Answer 21

A particle of light

Question 22

Threshold frequency

Answer 22

the minimum frequency of radiation required in order for an electron to be emitted from the surface of the metal.

Question 23

De Broglie Hypothesis

Answer 23

All particles have an associated wavelength given by

λ = h/p, Where h is the Planck constant and p is the momentum of the particle

Question 24

Wave Function

Answer 24

the square of the wave function amplitude is proportional to the probability density - the probability of finding a particle within a given volume.

Question 25

Heisenberg’s Uncertainty Principle

Answer 25

There is a fundamental limit to the degree of precision with which certain pairs of physical properties (eg. Position and momentum; Energy and time) can be measured.

Question 26

Count Rate

Answer 26

the number of ‘counts’ per second, as measured by a Geiger counter.