Einstein's Universe Final Exam 2025–2026
cosmology Accurate Real Exam Questions and
Verified Correcet answers
This document provides real, verified exam questions with correct answers for the
Einstein's Universe Final Exam, updated for the 2025–2026 academic year. It covers key
topics such as special and general relativity, spacetime concepts, gravitational waves,
black holes, cosmology, and the experimental evidence supporting Einstein’s theories.
Ideal for students seeking in-depth, exam-focused preparation with authentic question-
and-answer practice.
What is "special" about special relativity? What is the most general
principle of relativity? - <<answer>>>..-It's special in the sense that it is
limited to the special case of uniform motion.
-The most general principle of relativity would be that the laws of
physics are the same in all frames of reference.
Newton's Theory of Gravity - <<answer>>>..Newton's law of universal
gravitation states that any two bodies in the universe attract each other
with a force that is directly proportional to the product of their masses
and inversely proportional to the square of the distance between them.
What are two reasons that Newton's Theory of Gravity is not consistent
with special relativity? - <<answer>>>..-It is ambiguous as to which
distance between two objects to use in the mathematical expression of
the law of gravity. Since there is relative motion between the two
objects, the distance between the objects will be different as measured in
the two reference frames of these objects. That will give two different
values of the gravitational force. Which is correct?
,-Another reason it is not consistent with special relativity is that no
information can be transferred at a speed greater than the speed of light
(in a vacuum). But that mathematics of Newton's Theory of Gravity
predicts that the gravitational force is propagated instantaneously: the
Moon instantly knows if there is a change in the distance between it and
the Earth. How can anything or any information be transmitted at
infinite speed?
What astronomical observation existed in Einstein's day that Newton's
Theory of Gravity was not correctly explaining? - <<answer>>>..-There
was very little such experimental evidence. The only observation that
Newton's Theory of Gravity could not explain involved the motion of
the planet Mercury.
Did the astronomical observation represent a large or small discrepancy
between observation and Newton's Theory of Gravity? -
<<answer>>>..This was a very small discrepancy. Only very careful
astronomical observations detected it.
Was the discrepancy enough to convince physicists that Newton's
Theory of Gravity was not the final correct theory of gravity? -
<<answer>>>..No. Some thought that some other body might be
detected that exerted a gravitational influence on Mercury producing the
unpredicted deviation from Newton's gravitational theory. There were
too many things that Newton's Theory of Gravity explained: to abandon
it meant abandoning the solutions to a large number of solutions.
Describe Galileo's experiment involving falling objects near the surface
of the Earth. - <<answer>>>..Supposedly, Galileo dropped objects of
different weights from the Leaning Tower of Pisa All objects fall with
the same acceleration near the surface of the Earth: 32 feet per second
squared or 9.8 meters per second squared.
, Define inertial mass and gravitational mass in Newton's laws of physics.
- <<answer>>>..Inertial mass is measured by applying a force to an
object and producing an acceleration of that object. Take the applied
force and divide it by the resulting acceleration and you get the inertial
mass. This is an operational definition of inertial mass, using Newton's
Second Law of Motion, F = m a. So inertial mass is a measure of an
object's resistance to having its motion changed.
Gravitational mass is a measure of how strongly the Earth (or, by
extension any planet or star) pulls on an object through the gravitational
force. This is the mass that appears in the formula for Newton's Law of
Universal Gravitation: F = G m_1 m_2/r^2, where r is the distance
between the two objects of mass m_1 and m_2.
What is meant by the term "weightlessness"? Astronauts in orbit around
Earth in the International Space Station are said to be weightless because
gravity is not present. Is this true that gravity is not present on the
International Space Station or in the Space Shuttle when it orbits the
Earth? - <<answer>>>..The term weightlessness applies when one is in
a state of falling towards a large object like a planet or a star. That state
of falling includes a satellite or spacecraft in orbit around the Earth.
Though one feels as if they are weightless, as shown by a scale's reading
of 0 if one stood on it while falling, gravity is still present. If it wasn't
then the spacecraft would not stay in orbit around the Earth: it would fly
off into outer space.
Is there a frame of reference one can go into that seems to eliminate
gravity as Newton described it? - <<answer>>>..Yes such a frame
exists: a free-fall (free-float frame) frame. This frame of reference is
subject only to gravity and no forces such as electromagnetic forces or
nuclear forces. For example, it is like being in the elevator that had the
cable cut. You and everything in the elevator fall toward the earth with
the same acceleration so everything in the elevator appears to float - as if
everything was weightless.
cosmology Accurate Real Exam Questions and
Verified Correcet answers
This document provides real, verified exam questions with correct answers for the
Einstein's Universe Final Exam, updated for the 2025–2026 academic year. It covers key
topics such as special and general relativity, spacetime concepts, gravitational waves,
black holes, cosmology, and the experimental evidence supporting Einstein’s theories.
Ideal for students seeking in-depth, exam-focused preparation with authentic question-
and-answer practice.
What is "special" about special relativity? What is the most general
principle of relativity? - <<answer>>>..-It's special in the sense that it is
limited to the special case of uniform motion.
-The most general principle of relativity would be that the laws of
physics are the same in all frames of reference.
Newton's Theory of Gravity - <<answer>>>..Newton's law of universal
gravitation states that any two bodies in the universe attract each other
with a force that is directly proportional to the product of their masses
and inversely proportional to the square of the distance between them.
What are two reasons that Newton's Theory of Gravity is not consistent
with special relativity? - <<answer>>>..-It is ambiguous as to which
distance between two objects to use in the mathematical expression of
the law of gravity. Since there is relative motion between the two
objects, the distance between the objects will be different as measured in
the two reference frames of these objects. That will give two different
values of the gravitational force. Which is correct?
,-Another reason it is not consistent with special relativity is that no
information can be transferred at a speed greater than the speed of light
(in a vacuum). But that mathematics of Newton's Theory of Gravity
predicts that the gravitational force is propagated instantaneously: the
Moon instantly knows if there is a change in the distance between it and
the Earth. How can anything or any information be transmitted at
infinite speed?
What astronomical observation existed in Einstein's day that Newton's
Theory of Gravity was not correctly explaining? - <<answer>>>..-There
was very little such experimental evidence. The only observation that
Newton's Theory of Gravity could not explain involved the motion of
the planet Mercury.
Did the astronomical observation represent a large or small discrepancy
between observation and Newton's Theory of Gravity? -
<<answer>>>..This was a very small discrepancy. Only very careful
astronomical observations detected it.
Was the discrepancy enough to convince physicists that Newton's
Theory of Gravity was not the final correct theory of gravity? -
<<answer>>>..No. Some thought that some other body might be
detected that exerted a gravitational influence on Mercury producing the
unpredicted deviation from Newton's gravitational theory. There were
too many things that Newton's Theory of Gravity explained: to abandon
it meant abandoning the solutions to a large number of solutions.
Describe Galileo's experiment involving falling objects near the surface
of the Earth. - <<answer>>>..Supposedly, Galileo dropped objects of
different weights from the Leaning Tower of Pisa All objects fall with
the same acceleration near the surface of the Earth: 32 feet per second
squared or 9.8 meters per second squared.
, Define inertial mass and gravitational mass in Newton's laws of physics.
- <<answer>>>..Inertial mass is measured by applying a force to an
object and producing an acceleration of that object. Take the applied
force and divide it by the resulting acceleration and you get the inertial
mass. This is an operational definition of inertial mass, using Newton's
Second Law of Motion, F = m a. So inertial mass is a measure of an
object's resistance to having its motion changed.
Gravitational mass is a measure of how strongly the Earth (or, by
extension any planet or star) pulls on an object through the gravitational
force. This is the mass that appears in the formula for Newton's Law of
Universal Gravitation: F = G m_1 m_2/r^2, where r is the distance
between the two objects of mass m_1 and m_2.
What is meant by the term "weightlessness"? Astronauts in orbit around
Earth in the International Space Station are said to be weightless because
gravity is not present. Is this true that gravity is not present on the
International Space Station or in the Space Shuttle when it orbits the
Earth? - <<answer>>>..The term weightlessness applies when one is in
a state of falling towards a large object like a planet or a star. That state
of falling includes a satellite or spacecraft in orbit around the Earth.
Though one feels as if they are weightless, as shown by a scale's reading
of 0 if one stood on it while falling, gravity is still present. If it wasn't
then the spacecraft would not stay in orbit around the Earth: it would fly
off into outer space.
Is there a frame of reference one can go into that seems to eliminate
gravity as Newton described it? - <<answer>>>..Yes such a frame
exists: a free-fall (free-float frame) frame. This frame of reference is
subject only to gravity and no forces such as electromagnetic forces or
nuclear forces. For example, it is like being in the elevator that had the
cable cut. You and everything in the elevator fall toward the earth with
the same acceleration so everything in the elevator appears to float - as if
everything was weightless.
