Answer:
The Forces of Flight
At any given time, there are four forces acting upon an aircraft.
These forces are lift, weight (or gravity), drag and thrust. Lift is
the key aerodynamic force that keeps objects in the air. It is the
force that opposes weight; thus, lift helps to keep an aircraft in
the air. Weight is the force that works vertically by pulling all
objects, including aircraft, toward the center of the Earth. In order
to fly an aircraft, something (lift) needs to press it in the opposite
direction of gravity. The weight of an object controls how strong
the pressure (lift) will need to be. Lift is that pressure. Drag is a
mechanical force generated by the interaction and contract of a
solid body, such as an airplane, with a fluid (liquid or gas). Finally,
the thrust is the force that is generated by the engines of an
aircraft in order for the aircraft to move forward.
Explanation:
Geologists do not use a minerals color or streak to identify them because some minerals can have the same streak and color but the correct answer is
b) color
Answer:
1- b: 2- a : 3- c : 4- d
Explanation:
it starts 2 move away from strting point, then no motion, then moves toward the start, the slows up.
Answer:
iv) It is 9x bigger than before
Explanation:
As the amplitudes of the new speakers add directly with the original one, taking into account the phase that they have, the composed amplitude of the sound wave is as follows:
At = A + 4A -2A = 3 A
The intensity of the wave, assuming it propagates evenly in all directions, is constant at a given distance from the source, and can be expressed as follows:
I = P/A
where P= Power of the wave source, A= Area (for a point source, is equal to the surface area of a sphere of radius r, where is r is the distance to the source along a straight line)
For a sinusoidal wave, the power is proportional to the square of the amplitude, so the intensity is proportional to the square of the amplitude also.
If the amplitude changes increasing three times, the change in intensity will be proportional to the square of the change in amplitude, i.e., it will be 9 times bigger.
So, the statement iv) is the right one.
<span>Is the following sentence true or false? Newton's first law does object's mass concentration and its axis of rotation increases, its rotational inertia The bicycle wheels at rest have no angular momentum, and the bicycle will fall over easily.</span><span>
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