chapter 6 Flashcards
objects moving at a constant speed in a circle have what type of velocity and acceleration?
the velocity is always changing direction but the magnitude of the speed remains the same
the acceleration points towards the center
what is a period?
a period is the time interval it takes to complete a circle (T)
what is frequency
it is the # of revolutions per second (1/T)
what is the period of the earth around the sun?
what is the frequency?
the period is 1 year
it is 1 revolution/ 1 year
in uniform circular motion, what direction does the net force point towards?
it points the same direction as the acceleration (towards the center)
in a roller coaster, what is the apparent weight at the top?
the apparent weight is the magnitude of the contact forces that support you, this would be the normal force. It would be less than the actual weight (see explanation)
in a roller coaster, what is the apparent weight at the bottom
the normal force is the contact force that supports you, at the bottom of the track, the normal force has to be greater than the weight otherwise we would not accelerate upwards
so our apparent weight is greater
what is the critical speed
the critical speed is the slowest speed at which the car can remain in contact with the track and complete the circle
what is the normal force magnitude at the critical speed?
it is zero
what are circular orbits?
they are when you have a specific velocity to the point where you are falling at the same rate that the object you are falling towards is curving away
in an orbit, which direction does gravity point?
it points towards the center
what type of motion is a orbiting projectile? what type of force is it subject to?
it is in freefall where only gravity affects it
what does newtons law of gravity say?
it says that all objects have have mass have a force of attraction with all other objects that have mass
what is the inverse square law?
it states that the force of gravity is inversely proportional to the square of the distance between the objects
it states that the force is directly proportional to the product of the masses of the two objects
when a car goes around a curve, what forces are making the acceleration point towards the center?
weight, normal force, static friction
when a car is on the peak of the hill, what forces are present?
the weight force and the normal force
when a car is on the peak of a hill, what type of motion is it and where does the net force point?
it is a circular motion problem so the net force must point down towards the center
