Uniform Circular Motion
Constant speed but constantly changing direction.
Centripetal acceleration
An object moving uniformly in a circular path always has centripetal acceleration, which is an acceleration directed toward the center of the circle. "Center seeking" centripetal acceleration is a vector quantity whose magnitude is directly proportional t
Centripetal acceleration equation
Centripetal force
The force needed to keep an object moving in a circular path is called centripetal force, Fc. Centripetal force is the vector, directed toward the center of curvature that produces centripetal acceleration.
Centripetal force equation
Period
time to go around once
Period equation
T = (2pi x r)/v
Newton's Universal Law of Gravitation
According to Newton's universal law of gravitation, any two "bodies" attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Newton's Universal Law of Gravitation Equation
If the distance between the two masses is doubled, what happens to the magnitude of the gravitational force between the masses?
It is quartered.
If one of the two masses is doubled and the distance between the masses remains constant, what happens to the gravitational force?
The gravitational force is doubled.
Is there an outward force in circular motion? Explain.
No, there is only an inward motion causing a deviation from a straight line path.
What provides the centripetal force for the moon's orbit around the earth?
The force of gravity between the earth and the moon provide the centripetal force that maintains the orbit.
Compare the gravitational force the sun exerts on Earth to the gravitational force Earth exerts on the Sun.
The sun exerts the same gravitational force on Earth as Earth does on the Sun. (3rd Law)
As the distance between two masses increases, the gravitational force of attraction between them...
a. decreases
b. increases
c. remains the same
a. decreases
The magnitude of the gravitational force between two objects is 20 Newtons. If the mass of each object is doubled, the magnitude of the gravitational force between the objects is...
a. 5.0 N
b. 10 N
c. 20 N
d. 80 N
d. 80 N
What is the relationship between two point masses as a function of the distance between the masses?
Inverse
What is the relationship between the mass of an object and its distance from the center of Earth?
Constant
What is the relationship between weight and mass?
As mass increases, so does weight.
If on the x-axis there is mass and on the y-axis there is weight, what does the slope represent?
Acceleration
A 60 kg astronaut weighs 96 Newtons on the surface of the moon. Determine the acceleration due to gravity on the moon.
1.6 m/s^2
An 800 Newton person standing in an elevator. If the upward force of the elevator on the person is 600 Newtons the person is
a. at rest
b. accelerating upward
c. accelerating downward
d. moving downward at constant speed
b. accelerating upward
If the mass of the cart was doubled, the magnitude of the centripetal force on the cart would be...
a. halved
b. doubled
c. quartered
d. quadrupled
b. doubled
If the radius of the curvature of the path was doubled, the magnitude of the centripetal of the cart would be...
a. halved
b. doubled
c. quartered
d. quadrupled
a. halved
If the speed of the cart was doubled, the magnitude of the centripetal force on the cart would be...
a. halved
b. doubled
c. quartered
d. quadrupled
d. quadrupled
If the mass of the cart was halved, the magnitude of the centripetal acceleration would...
a. decrease
b. increase
c. remain the same
a. decrease
Which factor, when doubled would produce the greatest change in the magnitude of the centripetal force acting on the cart?
a. mass of the cart
b. radius of the curvature of the path
c. velocity of the cart
d. weight of the cart
c. velocity of the cart
As the time taken for a car to make one lap around a circular track decreases, the centripetal acceleration of the car...
a. decreases
b. increases
c. remains the same
b. increases
Which best describes the tangential acceleration of a cart moving at constant speed in a horizontal circle?
a. 0.0 m/s^2
b. 9.8 m/s^2
c. constant and directed radially toward the center of the curvature
d. constant and directed radially away from the cent
c. constant and directed radially toward the center of the curvature
Which best describes the centripetal acceleration of a ball of mass "m" moving at constant speed "v" in a horizontal circular path of radius "r"?
a. zero
b. constant in direction, but changing in magnitude
c. constant in magnitude, but changing in directi
b. constant in direction, but changing in magnitude
When doubled, what would produce the greatest change in the centripetal force acting on an object?
a. velocity
b. mass
c. radius
d. weight
a. velocity
If the speed were twice as great, what would the centripetal force be?
a. (1/2)Fc
b. 4Fc
c. 2Fc
d. 3Fc
b. 4Fc
Centripetal acceleration
Changing direction but constant magnitude if the speed and radius are kept constant.