Uniform Circular Motion
Dynamics of Circular Motion
Comparison studies
Calculations
Mixed Review
100
When an object moves in uniform circular motion, the direction of its acceleration is __.
Directed towards the center of the circular path.
100
A car goes around a circular curve on a horizontal road at constant speed. What is the direction of the friction force on the car due to the road?
Directed to the center of the circular path that the car is on.
100
The radius in case A is twice that of case B, the period is the same. How does the speed of case A compare to that of case B?
twice as fast
100
During their physics field trip to the amusement park, Tyler and Maria took a rider on the Whirligig. The Whirligig ride consists of long swings which spin in a circle at relatively high speeds. As part of their lab, Tyler and Maria estimate that the riders travel through a circle with a radius of 6.5 m and make one turn every 5.8 seconds. Determine the speed of the riders on the Whirligig.
7.0 m/s
100
If you stood on a planet having a mass four times that of Earth's mass, and a radius two times that of Earth's radius, you would weigh ___.
The same as you do on Earth.
200
What is the name given to the "force" that seems to push an object to the outside of its circular path? What is this "force" really?
Centrifugal force -- inertia!
200
When a car goes around a circular curve on a horizontal road at constant speed, what force causes it to follow the circular path?
The friction force from the road on the car.
200
The radius of case A is twice that of case B, the period is three times that of case B. How does the speed of Case A compare compare to that in case B?
2/3 times as fast
200
The tallest Ferris wheel in the world is located in Singapore. Standing 42 stories high and holding as many as 780 passengers, the Ferris wheel has a diameter of 150 meters and takes approximately 30 minutes to make a full circle. Determine the speed of riders (in m/s) on the Singapore Flyer.
0.26 m/s
200
The equation and direction of centripetal acceleration.
What is v^2/r and toward the center of the circle.
300
Each year, the moon gets a little bit farther away from the Earth, increasing the radius of its orbit. How does this change affect the length of the month?
A month will get longer.
300
A 1000-kg car is moving at 30 m/s around a horizontal unbanked curve whose diameter is 0.20 km. What is the magnitude of the friction force required to keep the car from sliding?
9000 N
300
The circle's radius in A is one half that of B, the velocity is the same. How does the acceleration of Case A compare to that of B?
2 times greater
300
Elmira, New York boasts of having the fastest carousel ride in the world. The merry-go-round at Eldridge Park takes riders on a spin at 18 mi/hr (8.0 m/s). The radius of the circle about which the outside riders move is approximately 7.4 m. Calculate the acceleration of the outside riders.
8.7 m/s/s
300
What is the name of Mrs. Rich's dog's name OR where did Mrs. Rich attend college?
Murray OR Wright State University
400
You are making a circular turn in your car on a horizontal road when you hit a big patch of ice, causing the force of friction between the tires and the road to become zero. While the car is on the ice, it ___.
... moves along a straight-line path in its original direction.
400
The crankshaft of a car rotates at 3000 rotations per minute. What is the period of motion of this crankshaft?
0.02 s
400
THe speed in case B is twice that of A, the radius is the same. How does the acceleration of Case A compare to that of B?
1/4 as much
400
A 76-kg pilot at an air show performs a loop de loop with his plane. At the bottom of the 52-m radius loop, the plane is moving at 48 m/s. Determine the normal force acting upon the pilot.
4.1 x 10^3 N
400
The equation for centripetal acceleration rearranged for radius.
square root (a*r)
500
Riding in the bed of a pick-up truck can be very dangerous. If the truck turns suddenly, the riders can be thrown from the truck bed. Why are the riders ejected from the bed?
The riders' inertia tends to keep them moving in the same straight-line motion while the truck turns beneath them. The walls of the bed of the pick-up truck are low so won't provide much centripetal force to hold the riders in the truck as it turns.
500
A 2.0-kg ball is moving with a constant speed of 5.0 m/s in a horizontal circle whose diameter is 1.0 m. What is the magnitude of the net force on the ball?
100 N
500
How does the NET FORCE of Case A compare to that of Case B?
4/3 as much
500
Sheila (m=62 kg) is riding the Demon roller coaster ride. The turning radius of the top of the loop is 12 m. Sheila is upside down at the top of the loop and experiencing a normal force which is one-half of her weight. Draw a free body diagram and determine Sheila's speed.
13 m/s
500
The centripetal force equation rearranged for velocity
What is the square root (F * r / m)?