Answer:
A. Is the one that the experimenter manipulates directly
Explanation:
The independent variable is the one that is manipulated during an experiment by the experimenter.
The dependent variable is the one that is effected by the independent variable in an experiment.
You're fishing for "polarization".
Answer:
0.231 N
Explanation:
To get from rest to angular speed of 6.37 rad/s within 9.87s, the angular acceleration of the rod must be

If the rod is rotating about a perpendicular axis at one of its end, then it's momentum inertia must be:

According to Newton 2nd law, the torque required to exert on this rod to achieve such angular acceleration is

So the force acting on the other end to generate this torque mush be:

Answer:
so initial speed of the rock is 30.32 m/s
correct answer is b. 30.3 m/s
Explanation:
given data
h = 15.0m
v = 25m/s
weight of the rock m = 3.00N
solution
we use here work-energy theorem that is express as here
work = change in the kinetic energy ..............................1
so it can be written as
work = force × distance ...................2
and
KE is express as
K.E = 0.5 × m × v²
and it can be written as
F × d = 0.5 × m × (vf)² - (vi)² ......................3
here
m is mass and vi and vf is initial and final velocity
F = mg = m (-9.8) , d = 15 m and v{f} = 25 m/s
so put value in equation 3 we get
m (-9.8) × 15 = 0.5 × m × (25)² - (vi)²
solve it we get
(vi)² = 919
vi = 30.32 m/s
so initial speed of the rock is 30.32 m/s