Physical and chemical changes are similar because matter experiences a change in state while undergoing either change.
First let us assign variables,
d = distance travelled
t = time it took
v = velocity of the commercial airline
In linear physics, the equation for velocity is given as:
v = d / t
Rewriting for d:
d = v t
We know that the distance to and from south America are equal
therefore:
d1 (going) = d2 (return)
Let us say that velocity of air is v3. Since going to South
America, the wind is against the direction of the plane and the return trip is
the opposite, therefore:
(v1 - v3) t1 = (v1 + v3) t2
(v1 – v3) 4 = (v1 + v3) 3.53
4 v1 – 4 v3 = 3.53 v1 + 3.53 v3
0.47 v1 = 7.53 v3
v1 = 16.02 v3
Since we also know that:
(v1 - v3) t1 = 784
(16.02 v3 – v3) * 4 = 784
60.085 v3 = 784
v3 = 13.05 mph
Therefore the speed of the plane in still air, v1 is:
v1 = 16.02 * 13.05
<span>v1 = 209.03 mph (ANSWER)</span>
<span> </span>
Ions were once atoms with the same number of electrons and protons. Since they have opposite charges atoms are neutral. When they become ions the lose or gain electrons and become unbalanced.These different charges are attracted to each other via electric forces<span>.</span>
When the capacitor is connected to the voltage, a charge Q is stored on its plates. Calling
the capacitance of the capacitor in air, the charge Q, the capacitance
and the voltage (
) are related by
(1)
when the source is disconnected the charge Q remains on the capacitor.
When the space between the plates is filled with mica, the capacitance of the capacitor increases by a factor 5.4 (the permittivity of the mica compared to that of the air):

this is the new capacitance. Since the charge Q on the plates remains the same, by using eq. (1) we can find the new voltage across the capacitor:

And since
, substituting into the previous equation, we find:

The distance from a 27 mw point source of electromagnetic waves where the electric field amplitude 0. 060 v/m will be 21.21 m .
Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.
The highest point of a wave is known as 'crest' , whereas the lowest point is known as 'trough'. Electromagnetic waves can be split into a range of frequencies. This is known as the electromagnetic spectrum.
c = 3 *
m/s
∈ = 8.85 *
/ N/ 
E = 0. 060 v/m
I = P / 4π
Also , I = c ∈
/2
= P / 4π I equation 1
substituting the value of I in equation 1
= 2 P / 4π (c ∈
)
= 2 * 27 *
/ 4 * 3.14 * 3 *
* 8.85 *
* 
r = 21.21 m
To learn more about Electromagnetic waves here
brainly.com/question/12392559
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