Fission

Question 1

What are the isotopes commonly used?

Answer 1

• ²³⁵U
• ²³⁹Pu

Question 2

What is induced fission?

Answer 2

• where the nucleus of an isotope is bombared by neutrons and neutrons are absorbed

Question 3

What are fission neutrons?

Answer 3

• neutrons released in fission event
• capable of causing a further fission event

Question 4

What is a chain reaction>

Answer 4

• chain reaction therefore possible in which fission neutrons produce firther fission events which release fission events and cause further fission events

Question 5

How is energy released in a fission event?

Answer 5

• occurs because the fragments repel each other as they are both positively charged with enough force to overcome the strong nuclear force holding them together
• fragment nuclei and fission neutrons gain Ek
  
  • binding energy per nucleon increases

Question 6

WHen does fusion occur?

Answer 6

• nuclear fusion can only take place if the two nuclei that are to be combined collide at high speed
• necessary to overcome electrostatic repulsion between the two nuclei so they can become close enough to interact through SNF

Question 7

How is solar energy produced?

Answer 7

• fusion
• high temp strips protons of electrons, referred to as plasma
• nuclei move at high speed because of temperature
  
  • large enough to overcome electrostatic force