Unit 7: Nuclear Physics

Question 1

Conditions for testing energy level?

Answer 1

1. High temperature 2. Low pressure

Question 2

How to distinguish the absorption and emission spectrum?

Answer 2

Emission - black with colorful lines; Absorption: Colorful lines with black slits.

Question 3

Temperature condition for absorption and emission spectrum

Answer 3

Absorption: Low temperature to allow absorption.
Emission: High temperature to allow emission.

Question 4

Limitations of the Bohr model?

Answer 4

1. It can only treat atoms with one electron.
2. Inconsistent with the uncertainty principle.
3. Does not predict the intensities of the spectral line.

Question 5

The constituents of an alpha particle?

Gamma?

Answer 5

1. 2 protons and 2 neutrons.

Only energy.

Question 6

The nature of decay and its meaning?

Answer 6

Random & Spontaneous - You can’t impact when and which particle is going to decay.

Question 7

Magnitude of the four fundamental forces in decreasing order?

Answer 7

Strong Nuclear Force strongest - Gravity weakest.

Strong, electromagnetic, weak, and gravitational

Question 8

What does Critical Mass mean?

Answer 8

The amount of necessary uranium 235 to trigger the chain reaction is called the critical mass.

Question 9

What’s the condition for Nuclear Fusion to take place?

Answer 9

1. High pressure.

2. High temperature.

Question 10

How to calculate the energy required to remove one nucleon from the nucleus?

Answer 10

Binding energy divided by the total number of nucleus.

Question 11

What does control rod do and what’s the function of the moderator?

Answer 11

Control rod: To absorb and control the amount of substances.
Moderator: To slow down the speed of neutron - allow chain reaction to take place (otherwise only small amount of energy will be created.)