Period/Frequency
The time it takes for an object to make one trip around a circular path
Period
True or False: objects in uniform circular motion do not travel at a constant speed.
False
The direction of centripetal force is always
Toward the center
Apparent weight is always equal to
Normal Force
The net force on an object is always pointing in what direction? What force exerts the net force?
Toward the center of the circle and friction
A runner completes 10 laps around a circular track in 850 seconds. What is the period of their motion??
At any point along a circular path, the direction of velocity will always be...
Tangent to the Path
What is the equation for centripetal force?
Fc=mv2/r
When a car is traveling over the top of a hill, the driver and passengers will have _____ compared to driving at the same speed on a flat road.
A lower apparent weight
What type of friction acts on a car while it is driving?
Static Friction
What is the period of the minute hand of a clock?
60 minutes or 3600 seconds
An object is in circular motion. The frequency of its motion is 7.0 Hz and its velocity is 20 m/s. What is the radius of its motion?
r=0.45m
A car with a mass of 1800 kg goes around an 18 m radius turn at a speed of 35 m/s. What is the centripetal force on the car?
Fc=122,500 N
The occupants of a car traveling at a speed of 25 m/s note that on a particular part of a road their apparent weight is 20% higher than their weight when driving at 25 m/s on a flat road.
Is that part of the road a hill, or a dip?
A dip
The driver replaces the tires (μ = 0.23) with new tires with μ = 0.50. How does this affect the maximum speed that the car can safely achieve on the curve? Draw the free-body diagram and indicate the direction of acceleration.
v=29 m/s for μ = 0.50
v=20 m/s for μ = 0.23
What is the relationship between period and frequency? AND how would I solve for period if given frequency?
The direction of acceleration is always
Toward the center of the circle or perpendicular to velocity
A ball on a string spins in a horizontal circle of radius 2.5 m with a speed of 3.0 m/s. The tension in the string is 5.4 N. What is the mass of the ball?
m=1.5 kg
At what velocity must a car drive over a hill of radius 80 m if the driver and car are to appear weightless?
v=28 m/s
A car can driver faster on a track if its coefficient of static friction ____ and/or the radius of the track _____.
Increases, increases
A pendulum swings with a frequency of 0.5 Hz. How long will it take to complete 30 cycles? What is the period?
t=60 seconds
T=2 seconds
An object is traveling in a circular path whose radius is 65m. Its acceleration is 3.0 m/s2. What is its velocity?
The first artificial satellite to orbit Earth, Sputnik, had a mass of 84 kg and orbited Earth every 5900 s at a distance from Earth's center of 6.4 x 106 m. What amount of gravitational force was acting on it?
F=610N
A pilot executes a vertical dive then follows a semi-circular arc until going straight up. At their lowest point, the normal force acting on the pilot is:
more than the weight and point up
As the mass of a car increases, its maximum speed on a curved track:
Does not change