Download Chapter 1: The Science of Biology

Unit 6: Rotational Motion
ABCD Review
“It’s for prizes, yo!”
The variable s is used to represent:
A) angular displacement
B) arc length
C) tangential distance
D) radial distance
All of the following are good reasons to
use radians instead of degrees when
describing circular motion except:
A) degrees can’t be negatives
B) the geometry of circles is already in
radians.
C) easier to express multiple rotations in
radians.
D) when using degrees the numbers can get
very large very quickly.
Omega is measured in ___________
A) rad/s2
B) m/s
C) m/s2
D) rad/s
A merry-go-round spinning at a constant
speed has _______________
A) tangential acceleration but no centripetal
acceleration
B) centripetal acceleration but no tangential
acceleration
C) both tangential and centripetal acceleration
D) it’s impossible to tell
The units of radians are __________
A) none
B) degrees
C) meters
D) π
Centrifugal force is ________________
A) a force directed toward the center
B) a force directed along the tangential path
C) the effects of Newton’s 1st Law
D) a combination of inertia and gravity
Centripetal acceleration is measured in
A) m/s
B) m/s2
C) rad/s
D) rad/s2
A child pedals her bicycle to go faster and
faster. The wheels have _____________
A) tangential acceleration but no centripetal
acceleration
B) centripetal acceleration but no tangential
acceleration
C) both tangential and centripetal acceleration
D) it’s impossible to tell.
The units of alpha are ____________
A) rad/s
B) m/s
C) m/s2
D) rad/s2
As the Earth spins, which people
experience the greatest tangential
velocity?
A) Santa’s elves (North pole)
B) North Koreans (in North Korea)
C) Peruvians (in Peru)
D) New Zealanders (In New Zealand)
If an object has both tangential and
centripetal acceleration, then it’s total
acceleration is ____________
A) the sum of both
B) the difference between them
C) found using the Pythagorean Theorem
D) it depends on the direction of each
A space station spins as in the diagram below in
order to create artificial gravity. Which picture
shows how the people living inside will live?
A
B
C
D
Which of the following is an incorrect
circular motion equation?
A) ωf2 = ωI2 + 2αθ
B) θ = ωIt + αt2
C) α = (ωf – ωi)/ t
D) They’re all correct
Where on Earth do objects fall the
fastest?
a) at the equator
b) at either the north or south poles
c) halfway between the equator and the poles
d) they fall at the same rate everywhere
A person standing directly on the South
Pole (rotational, not magnetic) has
________
A) equal amounts of alpha and omega
B) alpha but not omega
C) neither omega or alpha
D) more alpha than omega
A kid is sitting on a merry-go-round while
his friend spins it faster and faster. The
moment the kid flies off the ride:
A) the centripetal force was equal to the force of gravity
B) the centrifugal force was equal to the force of kinetic
friction
C) the centripetal force was equal to the force of static
friction
D) the centrifugal force was equal to the force of static
friction
A kid is sitting on a merry-go-round while
his friend spins it faster and faster. The
moment the kid flies off the ride, the
angular velocity is equal to:
A) the square root of (μsg)/r
B) mg + μsFN
C) mμsgrα
D) (gr)/mμs
Imagine a bicycle wheel with two beads on a spoke.
One bead is very close to the center and the other
bead is close to the rim. The wheel is rolling down a
hill. Which of the following statements is NOT true?
a) Both beads experience the same angular velocity and angular
accelerations
b) The tangential velocity is increasing for both beads but at
different rates
c) The tangential acceleration of the bead near the rim is always
higher than the bead near the center
d) The ratio of the two bead’s tangential velocities is a constant