D. definition of perihelion: the point in the orbit of a planet, asteroid, or comet at which it is closest to the sun. (the sun is an example of the star)
<span>1.7 rad/s
The key thing here is conservation of angular momentum. The system as a whole will retain the same angular momentum. The initial velocity is 1.7 rad/s. As the person walks closer to the center of the spinning disk, the speed will increase. But I'm not going to bother calculating by how much. Just remember the speed will increase. And then as the person walks back out to the rim to the same distance that the person originally started, the speed will decrease. But during the entire walk, the total angular momentum remained constant. And since the initial mass distribution matches the final mass distribution, the final angular speed will match the initial angular speed.</span>
I don't think I want to go into a lot of detail here, but the answer is
"sometimes true and sometimes false". I believe it depends on the
original difference between XC and XL, before XC began to change.
Answer:

ω = 0.0347 rad/s²
a ≅ 1.07 m/s²
Explanation:
Given that:
mass of the model airplane = 0.741 kg
radius of the wire = 30.9 m
Force = 0.795 N
The torque produced by the net thrust about the center of the circle can be calculated as:

where;
F represent the magnitude of the thrust
r represent the radius of the wire
Since we have our parameters in set, the next thing to do is to replace it into the above formula;
So;


(b)
Find the angular acceleration of the airplane when it is in level flight rad/s²

where;
I = moment of inertia
ω = angular acceleration
The moment of inertia (I) can also be illustrated as:

I = ( 0.741) × (30.9)²
I = 0.741 × 954.81
I = 707.51 Kg.m²

Making angular acceleration the subject of the formula; we have;

ω = 
ω = 0.0347 rad/s²
(c)
Find the linear acceleration of the airplane tangent to its flight path.m/s²
the linear acceleration (a) can be given as:
a = ωr
a = 0.0347 × 30.9
a = 1.07223 m/s²
a ≅ 1.07 m/s²
Horizontal forehead wrinkles are caused by contraction of the frontalis muscles. The frontalis muscles are two large fanlike muscles that extend from the eyebrow region to the top of the forehead. I think this is the answer