RIO SALADO PHY 111 FINAL EXAM 2026
CERTIFICATION EVALUATION QUESTIONS
AND COMPLETE SOLUTIONS FULL STUDY
GUIDE GRADED A+
⩥ What are the goals of string theory? (In class we discussed three
related goals).
Answer: 1) Resolve the incompatibility between Quantum mechanics
and general relativity
2) To unify the 4 forces: weak, strong, electromagnetic and gravity.
3) To explain the Fundamental Theory of Physics.
⩥ What are the four known fundamental forces of nature? Give an
example of each..
Answer: Gravitational- an apple falling towards the Earth
Electromagnetic- the touch of a hand, compass, a balloon on the hair,
radio, visible light, TV, electromagnetic waves.
Weak- radioactive decay (neutrons, muons)
Strong- Holds quarks together to make neutrons and protons. Holds
nucleus together. Nuclear decay results from strong force.
,⩥ In string theory what ARE fundamental particles such as electrons and
photons?.
Answer: Strings vibrating in different patterns
⩥ How does string theory force us to think differently about space?.
Answer: Makes us see things in different dimensions. There are more
dimensions than we can see with our naked eye. We as humans are
aware of 3 but there could be more.
⩥ What is the biggest conflict in modern day physics that string theory
hopes to resolve? What problems in physics require resolution of this
conflict in order to be more fully understood?.
Answer: The conflict between general relativity (galaxies, universe,
structures) and quantum mechanics (single scales, atoms, particles,
molecules).
The problem is that in the universe, there are some things like black
holes and the big bang theory that are simultaneously huge and small at
the same time
- we also learn later on that another huge discrepancy is that the universe
is not smooth like it was originally was thought to be- instead it has
"Quantum Foaming". General Relativity requires smooth space but
Quantum mechanics shows on an ultramicroscopic level, that this is not
true.
,⩥ Is string theory accepted?.
Answer: Yes and no. The yes part is it is intriguing and pulls together a
lot of elements, for example the discrepancy between quantum
mechanics and general relativity. The no part is that has not been proven
through experiments because there has never been a testable experiment
to validate the theory.
⩥ What is the reductionist viewpoint?.
Answer: If you understand fundamental particles, you understand all
forces and interactions that make up all matter; therefore we know
everything.
⩥ Lecture 3 and 4.
Answer:
⩥ According to James Clerk Maxwell, what is light?.
Answer: Electromagnetic wave
⩥ What precedence is there in physics for unification of forces?.
Answer: Maxwell unified with equations the electric and magnetic
forces to create the electromagnetic force to describe light.
, -later we also learned that Weinberg, Salam and Glashow brought
together Electromagnetism and Weak forces to create Electroweak
⩥ What two ideas (postulates) form the foundation for Einsteins special
theory of relativity?.
Answer: Speed of light travels at the same speed(in vacuum)
independent of an observer's state of motion
This is paradoxical because other things (like balls, other types of waves
besides E&M waves) don't behave that way
Principle of Relativity: the laws of physics do not depend on the
observers state of constant velocity or uniform motion
Ex: in a car at rest but the car next to you moves, you cannot tell if you
are moving or the car next to you is moving
⩥ Explain with a picture and a few words why the speed of light being a
constant for all observers regardless of their state of constant velocity
motion seems paradoxical?.
Answer: This is paradoxical because other things (like balls, other types
of waves besides E&M waves) don't behave that way
Picture ball where ball is thrown 10MPH and a person running in the
same direction the ball is moving at 5 MPH means the ball is moving at
the person at 5 MPH but if you do this with light you will never catch up
to light, no matter how fast the person s moving, the speed of light is
always 670 million MPH
CERTIFICATION EVALUATION QUESTIONS
AND COMPLETE SOLUTIONS FULL STUDY
GUIDE GRADED A+
⩥ What are the goals of string theory? (In class we discussed three
related goals).
Answer: 1) Resolve the incompatibility between Quantum mechanics
and general relativity
2) To unify the 4 forces: weak, strong, electromagnetic and gravity.
3) To explain the Fundamental Theory of Physics.
⩥ What are the four known fundamental forces of nature? Give an
example of each..
Answer: Gravitational- an apple falling towards the Earth
Electromagnetic- the touch of a hand, compass, a balloon on the hair,
radio, visible light, TV, electromagnetic waves.
Weak- radioactive decay (neutrons, muons)
Strong- Holds quarks together to make neutrons and protons. Holds
nucleus together. Nuclear decay results from strong force.
,⩥ In string theory what ARE fundamental particles such as electrons and
photons?.
Answer: Strings vibrating in different patterns
⩥ How does string theory force us to think differently about space?.
Answer: Makes us see things in different dimensions. There are more
dimensions than we can see with our naked eye. We as humans are
aware of 3 but there could be more.
⩥ What is the biggest conflict in modern day physics that string theory
hopes to resolve? What problems in physics require resolution of this
conflict in order to be more fully understood?.
Answer: The conflict between general relativity (galaxies, universe,
structures) and quantum mechanics (single scales, atoms, particles,
molecules).
The problem is that in the universe, there are some things like black
holes and the big bang theory that are simultaneously huge and small at
the same time
- we also learn later on that another huge discrepancy is that the universe
is not smooth like it was originally was thought to be- instead it has
"Quantum Foaming". General Relativity requires smooth space but
Quantum mechanics shows on an ultramicroscopic level, that this is not
true.
,⩥ Is string theory accepted?.
Answer: Yes and no. The yes part is it is intriguing and pulls together a
lot of elements, for example the discrepancy between quantum
mechanics and general relativity. The no part is that has not been proven
through experiments because there has never been a testable experiment
to validate the theory.
⩥ What is the reductionist viewpoint?.
Answer: If you understand fundamental particles, you understand all
forces and interactions that make up all matter; therefore we know
everything.
⩥ Lecture 3 and 4.
Answer:
⩥ According to James Clerk Maxwell, what is light?.
Answer: Electromagnetic wave
⩥ What precedence is there in physics for unification of forces?.
Answer: Maxwell unified with equations the electric and magnetic
forces to create the electromagnetic force to describe light.
, -later we also learned that Weinberg, Salam and Glashow brought
together Electromagnetism and Weak forces to create Electroweak
⩥ What two ideas (postulates) form the foundation for Einsteins special
theory of relativity?.
Answer: Speed of light travels at the same speed(in vacuum)
independent of an observer's state of motion
This is paradoxical because other things (like balls, other types of waves
besides E&M waves) don't behave that way
Principle of Relativity: the laws of physics do not depend on the
observers state of constant velocity or uniform motion
Ex: in a car at rest but the car next to you moves, you cannot tell if you
are moving or the car next to you is moving
⩥ Explain with a picture and a few words why the speed of light being a
constant for all observers regardless of their state of constant velocity
motion seems paradoxical?.
Answer: This is paradoxical because other things (like balls, other types
of waves besides E&M waves) don't behave that way
Picture ball where ball is thrown 10MPH and a person running in the
same direction the ball is moving at 5 MPH means the ball is moving at
the person at 5 MPH but if you do this with light you will never catch up
to light, no matter how fast the person s moving, the speed of light is
always 670 million MPH
