Resnick/ Buggé: Circular Motion 2
v 2.1: A battery-powered toy car moves at constant speed
across the top of a circular hump, as shown in the
illustration to the right. Indicate the direction of the
acceleration of the car at the top of the hump. Draw a force
diagram for the car when passing across the top of the
hump. Make the force arrows the correct relative lengths.
Write in words if the results of the first two cells of this
table are consistent with Newton’s second law.
2.2: Fill in the table that follows with the necessary information.
Rollercoaster
situation; circle the
system.
(a) The roller coaster
car glides at constant
speed along a
frictionless, level
track.
Indicate
 the direction Draw a force
a
of  .
diagram
(b) The roller coaster
car moves along a
frictionless circular dip
in the
track.
To
(c) The roller coaster
car moves inverted
past the top of a
frictionless loop-theloop.
x Apply ∑Fradial =
m v2/r.
Resnick/ Buggé: Circular Motion 2
2.3: The Seattle Phantom Park Ferris wheel is about 10 m in radius and takes 15 s to complete
one rotation. Brigit (60-kg) sits in one of the seats. Determine the magnitude of the normal force
of the seat on Brigit at the top and bottom of the ride.
2.4: Suppose the loop in the figure has a 16-m diameter. How fast must the roller coaster car
move across the top of the loop so that the force that the seats exert on its riders is half the force
that the Earth exerts on them?
2.5: The third turn at the Alamo Cart Dirt Speedway is tilted at 300 and has a 240-m radius.
Determine the speed of a Cart Car going around that turn, assuming the car has no help from
friction.