Unit 3: 3.4

Question 1

Half-life

Answer 1

Length required for half of a given sample of radioactive isotope to decay

Question 2

• helium nucleus
• +2 electric charge
• shieled by a piece of paper or dead skin cells.

Answer 2

Alpha particle

Question 3

• same as an electron

* shielded by a piece of wood, several pieces of paper

Answer 3

Beta particle

Question 4

• high energy photon of light

* requires heavy shielding of lead or steel

Answer 4

Gamma rays