Physics Multiple Choice Part 2
A ball is thrown upward with a speed of approximately 20 m/s. Which of the following sets of numbers are good estimates of the ball's velocity 1 second, 2 seconds and 3 seconds later?
10 m/s, 0 m/s, -10 m/s
An object is dropped from rest and free falls to the ground. How far has it fallen in the 1.5 seconds after being dropped?
11.0 m
An object is dropped from rest and free falls to the ground. How fast will it be moving 1.5 seconds after being dropped?
14.7 m/s
Riders on an amusement park ride called the Giant Drop free fall for 2.8 seconds before the safety system brings them to an abrupt halt. How fast are the riders moving at 2.8 seconds?
27.4
Riders on an amusement park ride called the Giant Drop free fall for 2.8 seconds before the safety system brings them to an abrupt halt. How far do riders free fall during these 2.8 seconds?
38.4 m
Whic one of the following is most likely a free-falling object?
A feather falling through a vacuum chamber
The slope of a velocity-time graph represents the _____ of the object.
Acceleration
Which is the best definition of a free-falling object?
An object whose motion is influenced by just one force - the force of gravity
The position-time graph for an object with a velocity that is changing would be a line with ____.
Changing slope
A skydiver has fallen for several seconds and has accumulated enough air resistance to reach a terminal velocity. The skydiver is now in a state of free-fall.
False
An object that is moving rightward MUST have a rightward acceleration.
False
Which of the following is true of a free-falling object? Select all that apply
Gravity is the only force of influence It has an acceleration It's velocity is changing
Which statement best describes a free-falling object?
It is an object that is under the sole influence of gravity
What does the acceleration of gravity refer to?
It refers to the acceleration of a free falling object.
The position-time graph for an object with a negative velocity would be a line with ____.
Negative slope
Which one of the following variables would affect the acceleration of a free falling object?
Nonsense! None of these variables would affect the free fall acceleration of an object.
Which one of the following objects would free fall to the ground with the greatest acceleration?
Nonsense! They all free fall with the same acceleration.
As we have learned, the quantity that we call acceleration is a vector; it has a magnitude and a direction. Which statement describes the acceleration of a free falling object?
The acceleration has both a constant value and a constant direction.
A ball is dropped from the ceiling and free falls to the floor. Which one of the following statements regarding the ball's motion is incorrect?
The acceleration of the ball increases as it falls to the ground.
Which one of the following represents the displacement of an object?
The area under the line of a velocity-time graph.
A ball is dropped from the ceiling and free falls to the floor. Which one of the following statements regarding the ball's motion is incorrect?
The position of the ball changes by the same amount each second that it falls.
How does the free fall acceleration of a ball dropped from rest compare to the free fall acceleration of a ball that is thrown upward?
The two balls will have the same free fall acceleration.
Evaluate this statement: A falling object accelerates at 9.8 m/s/s/s.
This statement is only true of free-falling objects, upon which gravity is the only force of influence.
A car can be moving to the right and have a leftward acceleration.
True
An object can be moving upward and have a downward acceleration.
True
The slope of a position-time graph represents the _____ of the object.
Velocity
The position-time graph for an object with a velocity of zero would be a line with ____.
Zero slope
The velocity-time graph for an object with an acceleration of zero would be a line ____.
Zero slope
Objects that are free-falling will ___________. (Select all that aply)
change their velocity by the same amount each second. have an unchanging acceleration.
The velocity-time graph for an object with a constant positive acceleration would be a line ____.
that is straight and has positive slope
If a free-falling rock were equipped with a speedometer, one would observe that _______.
the speed would change by 9.8 m/s each second of its fall.
