Circular Motion and Gravitation
What happens when you swing a bucket full of water over your head in a vertical circle and do not stop?
The water spills out once upside down because gravity overcomes centripetal force.
The bucket empties immediately as there is no force acting on the water.
The water stays inside due to centripetal force acting on it.
The water rises up out of the bucket because of free body motion.
If three identical space stations are placed equally spaced along Earth’s equator, what impact will increasing Earth’s rotation rate have on astronauts inside each station?
No change as gravity depends solely on mass & radius not rotation rate
They will experience less gravity due to decreased centripetal acceleration
Increase apparent weight due to stronger centrifugal effects
Decrease apparent weight since increasing spin reduces effective gravity
When comparing a planet in an elliptical orbit around a star to another planet in a circular orbit with equivalent average distance, what difference may be observed about their velocities?
The planet in an elliptical orbit varies its velocity along its path while maintaining constant angular momentum whereas velocity remains constant in a circular orbit.
The planet in the circular orbit sporadically increases and decreases velocity due to uniform circular acceleration constants.
Both planets maintain constant velocities throughout their respective orbits due to their consistent average distances from their star.
The planet in an elliptical orbit has a constantly faster velocity due to increased energy within non-circular paths.
How does total system momentum change when two ice skaters push off each other on frictionless ice?
Total system momentum decreases due to internal forces canceling out
Total system momentum increases due to their muscles' action
Total system momentum changes unpredictably because it depends on individual skater masses
Total system momentum remains constant
What type of energy transformation occurs in a satellite orbiting Earth?
Thermal energy to kinetic energy
Kinetic energy to potential energy and back
Chemical energy to thermal energy
Nuclear energy to electrical energy
Inertial frames of reference are also called
Tesla frames of reference
Newtonian frames of reference
Galilean frames of reference
Einstein frames of reference
Which scenario describes how velocity changes for an object in stable circular orbit around earth when its altitude decreases without propulsion added?
Slows down because conservation angular momentum keeps velocity same despite smaller radius
Steady pace maintained as height drop balances out with increase earth pulling
Speeds up due larger earth pull causing faster movement
Remains steady until atmospheric drag reduces velocity overtime

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Which quantity remains constant for an object in uniform circular motion?
Force
Speed
Acceleration
Velocity
Which expression correctly describes the relationship between the net force acting upon an object moving in a circle and its centripetal acceleration?
The net force is equal to the product of mass and centripetal acceleration ()
The net force is equal to the mass divided by the triple centripetal acceleration ()
The net force is equal to half the mass multiplied by centripetal acceleration ()
The net force is equal to twice the mass multiplied by centripetal acceleration ()
To calculate gravitational force between two masses we need their masses & distance between them ; what instrument could be used for measuring mass?
Altimeter
Scale
Spectrometer
Odometer