Particles

What does “Specific” mean?

Per unit mass

How does Carbon Dating work?

Living organisms contain a constant ratio of C-12 : C-14

When organism dies, it stops taking in Carbon, and C-14 begins to decay

By find the ratio of C-12:C-14 we can work out the number of half lives, thus the age of the organism

How do you calculate Relative Atomic Mass given the relative abundance of isotopes?

Avg.mass = [(m₁ %₁) + (m₂ * %₂)] / [100]

How do you find the average specific charge of a sample of ions or isotopes?

Find the individual specific charges

Use the relative abundances to find the average

What is the quark combination for a positive, neutral, and negative Kaon?

positive : up anti-strange

neutral : down anti-strange

negative : anti-up strange

Which energy level does E₁ refer to in : hf = E₁ - E₂ ?

The higher energy level

Subtracting a more negative number will give a positive number

Over what range is the SNF attractive?

0.5 → 3 fm

Give the 4 required examples of weak interactions

Beta plus and minus decay

Electron capture

Electron - proton collisions

Give an example of a Kaon (K⁺) decay

K⁺ → pi⁺ + pi⁰

K⁺ → pi⁺ + pi⁺ + pi⁰

What is evidence for the existence of energy levels in atoms?

Line spectra

What are the key points when explaining how the photoelectric effect evidences the particulate nature of light?

Increasing intensity while f<f₀ does not cause photoelectric emission.

Increasing intensity when f >= f₀ increases the number of photoelectrons emitted but not their maximum energy.

Increasing f past f₀ increases the maximum kinetic energy.

Key point : wave energy relies on intensity but here the energy appears to rely on frequency. There would not be a minimum frequency required if light only behaved as a wave as energy would accumulate gradually. The energy therefore must be transferred to the electrons in a one-to-one collision between a photon and an electron in the surface of the metal.