RM-RK-1
A car is traveling clockwise around a circular track, as shown in the figure. If the car is traveling at a constant rate, what is the sign of the car's following angular quantities?
If the car is slowing down, what is the sign of the car's following angular quantities?
RM-RK-2
A ladybug sits at the outer edge of a merry-go-round, and a gentleman bug sits halfway between her and the axis of rotation. The merry-go-round makes a complete revolution once each second. The gentleman bug's angular speed is
1. half the ladybug's.
2. the same as the ladybug's.
3. twice the ladybug's.
4. impossible to determine
RM-RK-3
A 40-cm-radius disk begins rotating from rest and spins up uniformly to an angular speed of 4500 rev/min in 5 seconds.
(a) What is the angular acceleration (in rad/s2) of the disk?
(b) How far (in meters) does a point on the edge travel in 3 s?
(c) What is the linear acceleration vector of a point on the edge of the disk at 3 s?
RM-RK-4
A ladybug sits at the outer edge of a merry-go-round that is turning and slowing down. At the instant shown in the figure, the radial component of the ladybug's (linear) acceleration is
1. in the +x direction.
2. in the -x direction.
3. in the +y direction.
4. in the -y direction.
5. in the +z direction.
6. in the -z direction.
7. zero.
RM-RK-5 (Use previous image)
The tangential component of the ladybug's (Cartesian) acceleration is
1. in the +x direction.
2. in the -x direction.
3. in the +y direction.
4. in the -y direction.
5. in the +z direction.
6. in the -z direction.
7. zero.
RM-RK-6
A ladybug sits at the outer edge of a merry-go-round, and a gentleman bug sits halfway between her and the axis of rotation. The merry-go-round makes a complete revolution once each second. The gentleman bug's speed is
1. greater than the ladybug's
2. less than the ladybug's
3. equal to the ladybug's
4. impossible to determine without knowing radii
RM-RK-7
A car is traveling clockwise around a circular track as shown in the figure. If the car is speeding up, sketch a vector coming off the car in the direction of the car's linear acceleration.
RM-RK-8
After fixing a flat tire on a bicycle you give the 72-cm-diameter wheel a spin and let go. Consider right after you’ve let go of the wheel, and it’s spinning, as the initial time. (a) If its initial angular speed was 6.15 rad/s and it rotated 13.2 revolutions before coming to rest, what was the magnitude of its average angular acceleration? (b) How long (time) did the wheel rotate before coming to rest? (c) What was the initial linear acceleration of a point on the rim of the tire?
RM-RK-9
The plot describes the angular velocity versus time for an object moving around 2-m-radius circle . Four time segments, A, B, C, and D have been labeled. Assume the initial angle is zero.(a) What is the object’s angular acceleration during time segment B (5 s < t < 10 s)? (b) How many radians does the object subtend (go through) during time segment A (0 s < t < 5 s)? (c) What is the linear speed of the object during the time segment in which the object is undergoing uniform circular motion? Extra credit: at what time, other than t = 0 s, is the object’s net displacement equal to zero?