PHYS Exam 3 Questions & Answers
2024/2025
frame of reference - ANSWERSMotion in the Universe, as seen by some specific observer
Inertial frame of reference - ANSWERSMotion in the Universe, as seen by non-accelerating
observer
Suppose I am in an inertial reference frame. What is my velocity, as measured from my own
frame?
A. Zero
B. Positive
C. Negative - ANSWERSA. Zero
You are not moving
Suppose I'm on an airplane, flying at 350. I throw my keys upward. Will I be able to catch them?
A. No
B. Yes - ANSWERSB. Yes
my keys will fall back down into my lap
Galilean Relativity - ANSWERS- Galilean relativity only works for motion that is much less than
the speed of light.
- In the Galilean regime, velocities add and subtract.
Suppose you're walking on a moving platform.
If you're walking with the platform - ANSWERSyour speed adds to the platforms speed
, Suppose you're walking on a moving platform.
If you're walking against the platform - ANSWERSyour speed subtracts from the platform's
speed
Suppose a person is walking down an escalator. The escalator is moving 2 mph upward with
respect to the ground, and the person is walking 3 mph downward with respect to the escalator.
What is the person's velocity with respect to the ground?
A.1 mph upward
B.5 mph upward
C.5 mph downward
D.1 mph downward - ANSWERSD. 1 mph downhill
Since the person and the escalator are moving in opposite directions, their speeds subtract
Suppose Car A is moving 60 mph, and Car B is moving 70 mph, both northbound, as measured
from the ground. What is Car A's velocity relative to Car B?
A.0 mph
B.10 mph northbound
C.10 mph southbound
D.130 mph northbound
E.130 mph southbound - ANSWERSC. 10 mph southbound
In the ground frame, Car B is moving 10 mph faster
Car B sees Car A falling behind - that is moving backward (southbound) at 10 mph
A particle cannot travel _____ than c, the speed of ligh - ANSWERSfaster
Massive particles like electrons move at ____ than c - ANSWERSless
2024/2025
frame of reference - ANSWERSMotion in the Universe, as seen by some specific observer
Inertial frame of reference - ANSWERSMotion in the Universe, as seen by non-accelerating
observer
Suppose I am in an inertial reference frame. What is my velocity, as measured from my own
frame?
A. Zero
B. Positive
C. Negative - ANSWERSA. Zero
You are not moving
Suppose I'm on an airplane, flying at 350. I throw my keys upward. Will I be able to catch them?
A. No
B. Yes - ANSWERSB. Yes
my keys will fall back down into my lap
Galilean Relativity - ANSWERS- Galilean relativity only works for motion that is much less than
the speed of light.
- In the Galilean regime, velocities add and subtract.
Suppose you're walking on a moving platform.
If you're walking with the platform - ANSWERSyour speed adds to the platforms speed
, Suppose you're walking on a moving platform.
If you're walking against the platform - ANSWERSyour speed subtracts from the platform's
speed
Suppose a person is walking down an escalator. The escalator is moving 2 mph upward with
respect to the ground, and the person is walking 3 mph downward with respect to the escalator.
What is the person's velocity with respect to the ground?
A.1 mph upward
B.5 mph upward
C.5 mph downward
D.1 mph downward - ANSWERSD. 1 mph downhill
Since the person and the escalator are moving in opposite directions, their speeds subtract
Suppose Car A is moving 60 mph, and Car B is moving 70 mph, both northbound, as measured
from the ground. What is Car A's velocity relative to Car B?
A.0 mph
B.10 mph northbound
C.10 mph southbound
D.130 mph northbound
E.130 mph southbound - ANSWERSC. 10 mph southbound
In the ground frame, Car B is moving 10 mph faster
Car B sees Car A falling behind - that is moving backward (southbound) at 10 mph
A particle cannot travel _____ than c, the speed of ligh - ANSWERSfaster
Massive particles like electrons move at ____ than c - ANSWERSless
