WorksheetsChapter 8: Rotational motion
Total questions: 30
Worksheet time: 15mins
1 revolution:
57°
90°
180°
360°
The SI unit of angular momentum is J s. It can also be expressed as:
kg m s−1
kg m2 s−1
kg m2 s−2
kg m−2 s−1
Revolution/minute is the unit for
Angular displacement
Angular acceleration
Angular velocity
Time
Time rate of change of angular velocity is called:
Angular momentum
Angular displacement
Angular acceleration
Time
The angular acceleration is produced by
Momentum
Torque
Pressure
Power
Moment of inertia is equal to:
m2r
m2r2
m r
m r2
Moment of inertia is measured in:
kg m2
kg m−2
N s
rad s−1
The angular momentum is given by:
m ω
ω × F
r × F
r × P
The direction of linear velocity of body moving in a circle is:
Along the axis of rotation
Along the tangent
Directed towards the center
Directed away from the center
The relation between linear and angular acceleration is
a =a ×r
a = r ×α
r = a× α
α = a×r
Unit of angular velocity in SI unit is:
sRad
sm
sDegree
sRevolution
A gymnast spinning with his arms out stretched pull his arms inward. What is the angular speed?
The angular speed decreases
The angular speed increases
Neither increases nor decrease
Both increases and decreases
When torque acting on a system is zero, which of the following will be constant:
Linear momentum
Force
Angular momentum
Impulse
Angular displacement is usually express in units of
Meters
Radians
Revolutions
Arcs
A boy and a girl are riding on a merry-go-round which is turning at a constant rate. The boy is near the outer edge, and the girl is closer to the center. Who has the greater angular displacement?
The boy
The girl
Both have the same non-zero angular displacement.
Both have zero angular displacement.
A boy and a girl are riding on a merry-go-round which is turning at a constant rate. The boy is near the outer edge, and the girl is closer to the center. Who has the greater linear speed?
The boy
The girl
Both have the same non-zero translational velocity.
Both have zero translational velocity.
What is the quantity used to measure an object's resistance to changes in rotation?
Mass
Moment of inertia
Torque
Angular velocity
If a constant net torque is applied to an object, that object will
Rotate with constant angular velocity.
Rotate with constant angular acceleration.
Having an increasing moment of inertia
Having a decreasing moment of inertia.
An ice skater performs a pirouette (a fast spin) by pulling in his outstretched arms close to his body. What happens to his moment of inertia about the axis of rotation?
It does not change
It increases
It decreases
It changes, but it is impossible to tell which way
An ice skater performs a pirouette (a fast spin) by pulling in his outstretched arms close to his body. What happens to his angular momentum about the axis of rotation?
It does not change.
It increases
It decreases
It changes, but it is impossible to tell which way
The Earth moves about the Sun in an elliptical orbit. As the Earth moves close to the Sun, then which of the following best describes the orbiting speed of the Earth about the Sun?
Increases
Decreases
Remains constant
Impossible to tell
The Earth orbits the Sun in an elliptical orbit. Ignore any friction which may be present. What happens over time to the Earth's angular momentum about the Sun?
It continually increases.
It continually decreases.
It remains constant.
It increases during some parts of the orbit, and decreases during others.
Angular acceleration is expressed in units of
Meters per second squared.
Radians per second squared.
Alphas per second squared
Arcs per second squared.
A boy and a girl are riding a merry-go-round which is turning at a constant rate. The boy is near the outer edge, while the girl is closer to the center. Who has the greater tangential acceleration?
The boy
The girl
Both have the same non-zero tangential acceleration.
Both have zero tangential acceleration.
A boy and a girl are riding on a merry-go-round which is turning at a constant rate. The boy is near the outer edge, and the girl is closer to the center. Who has the greater angular speed?
The boy
The girl
Both have the same non-zero angular velocity.
Both have zero angular velocity
A uniform object has mass M and radius R. If these are increased to 2M and 3R, what happens to the sphere's moment of inertia about a central axis?
Increases by a factor of 6
Increases by a factor of 12
Increases by a factor of 18
Increases by a factor of 54
Two equal forces are applied to a door at the doorknob. The first force is applied perpendicular to the door; the second force is applied at 30e to the plane of the door. Which force exerts the greater torque?
The first applied perpendicular to the door
The second applied at an angle
Both exert equal non-zero torques
Both exert zero torques
Two equal forces are applied to a door. The first force is applied at the midpoint of the door; the second force is applied at the doorknob. Both forces are applied perpendicular to the door. Which force exerts the greater torque?
The first at the midpoint
The second at the doorknob
Both exert equal non-zero torques
Both exert zero torques
The rotational inertia of a wheel about its axle does not depend upon its:
Diameter
Mass
Distribution of mass
Speed of rotation
The angular velocity vector of a spinning body points out of the page. If the angular acceleration vector points into the page then:
The body is slowing down
The body is speeding up
The body is starting to turn in the opposite direction
The axis of rotation is changing orientation
