Conceptual Physics - Circular Motion
Practice
When an ice skater does a pirouette turn in her routine at the Olympics, she _______
about her axis - Answer-rotates
/.A straight line about which rotation takes place is called - Answer-axis
/.When a twirling ice skater brings her arms inward, her rotational speed - Answer-
increases
/.Whereas a rotation takes place about an axis that is internal, a revolution takes place
about an axis that is - Answer-external
/.Which part of Earth's surface has the greatest rotational speed about the Earth's axis?
- Answer-All of the above
/.Which place on Earth's surface has the greatest LINEAR SPEED relative the Earth's
axis? - Answer-Africa
/.Which state in the US has the greatest TANGENTIAL speed as Earth rotates around
its axis - Answer-Hawaii
/.If a boy sitting on a horse near the inner rail of the merry-go-round has a rotational
speed of 4RPM and a tangential speed of 2 m/s, what will be the rotational speed of his
sister who is sitting on a horse on the outer rail? - Answer-4 RPM
/.Inside Biker Bob's space station is a ladder that extends from the inner surface of the
rin to the central axis. Bob climbs the ladder towards the center. Point A is at the floor,
point B is halfway to the center and point C is at the center of the axis.
Rank the LINEAR SPEEDS of Bob relative to the center of the station, from G to L -
Answer-A > B > C
/.If a boy sitting on a horse near the inner rail of the merry go round has a rotational
speed of 4 RPM and a tangential speed of 2 m/s, what will be the tangential speed of
his sister who is sitting on a horse on the outer rail, THREE times farther away?
v = r*w
3(2 m/s) - Answer-6 m/s
/.Solve for the tangential speed of a passenger on a Ferris wheel that has a radius of 5
m and rotates once in 30s. v = d/t = 2[pi]r/t
r = 5m
t = 30s - Answer-v = 2[pi](5m)/30s
Practice
When an ice skater does a pirouette turn in her routine at the Olympics, she _______
about her axis - Answer-rotates
/.A straight line about which rotation takes place is called - Answer-axis
/.When a twirling ice skater brings her arms inward, her rotational speed - Answer-
increases
/.Whereas a rotation takes place about an axis that is internal, a revolution takes place
about an axis that is - Answer-external
/.Which part of Earth's surface has the greatest rotational speed about the Earth's axis?
- Answer-All of the above
/.Which place on Earth's surface has the greatest LINEAR SPEED relative the Earth's
axis? - Answer-Africa
/.Which state in the US has the greatest TANGENTIAL speed as Earth rotates around
its axis - Answer-Hawaii
/.If a boy sitting on a horse near the inner rail of the merry-go-round has a rotational
speed of 4RPM and a tangential speed of 2 m/s, what will be the rotational speed of his
sister who is sitting on a horse on the outer rail? - Answer-4 RPM
/.Inside Biker Bob's space station is a ladder that extends from the inner surface of the
rin to the central axis. Bob climbs the ladder towards the center. Point A is at the floor,
point B is halfway to the center and point C is at the center of the axis.
Rank the LINEAR SPEEDS of Bob relative to the center of the station, from G to L -
Answer-A > B > C
/.If a boy sitting on a horse near the inner rail of the merry go round has a rotational
speed of 4 RPM and a tangential speed of 2 m/s, what will be the tangential speed of
his sister who is sitting on a horse on the outer rail, THREE times farther away?
v = r*w
3(2 m/s) - Answer-6 m/s
/.Solve for the tangential speed of a passenger on a Ferris wheel that has a radius of 5
m and rotates once in 30s. v = d/t = 2[pi]r/t
r = 5m
t = 30s - Answer-v = 2[pi](5m)/30s
