Points 100 Questions 51
Instructions
Note: To simplify calculations, you may use g - 10 m/s2 in all problems.
Attempt History
Attempt Score
LATEST Attempt 1 92.15 out of 100
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, Score for this attempt: 92.15 out of 100
Submitted May 11 at 11:56am
This attempt took 2,450 minutes.
Question 1 1..97 pts
A person throws a marble straight up into the air, releasing it a short
height above the ground and catching it at that same height. If air
resistance is negligible, which of the following graphs of position y versus
time t is correct for the motion of the marble as it goes up and then comes
down?
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ct .97 pts
Question 2
A rocket lifts a payload upward from the surface of Earth. The radius of
Earth is R, and the weight of the payload on the surface of Earth is W.
The force of Earth's gravity on the payload is W/2 when the rocket's
distance from the center of Earth is
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, 2R
R
4R
Question 3 1..97 pts
An object is thrown with an initial speed v near the surface of Earth.
Assume that air resistance is negligible and the gravitational field is
constant. If the object is thrown vertically upward, the direction and
magnitude of its acceleration while it is in the air is
downward and increasing
downward and constant
upward and constant
downward and decreasing
upward and decreasing
Question 4 1..97 pts
An object is thrown with an initial speed v near the surface of Earth.
Assume that air resistance is negligible and the gravitational field is
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, constant. If the object is thrown horizontally, the direction and magnitude
of its acceleration while it is in the air is
downward and decreasing
downward and constant
downward and increasing
upward and constant
upward and decreasing
Question 5 1..96 pts
An object weighing 120 N is set on a rigid beam of negligible mass at a
distance of 3 m from a pivot, as shown above. A vertical force is to be
applied to the other end of the beam a distance of 4 m from the pivot to
keep the beam at rest and horizontal. What is the magnitude F of the
force required?
120N
160 N
90 N
30 N
10 N
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