Answer:
Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.
Explanation:
Answer:
Sum of the forces will be equal to 3.479 N
Explanation:
We have given two same forces are oriented at an angle of 38°
Magnitude of each force is given 
We have to find the sum of the forces
Sum of the forces will be equal to

So sum of the forces will be equal to 
So sum of the force will be equal to 3.479 N
Answer:
480J
Explanation:
Using the formula:
Delta U = Q - W
Q:Heat (J)
Delta U: Changes in internal Energy (J)
W:Work (J)
We can plug in the give numbers, Q and W.
Delta U = 658J - 178J = 480J
Sattelites don't need any fuel to stay in orbit. The applicable law is...."objects in motion tend to stay in motion". Having reached orbital velocity, any such object is essentially "falling" around the earth. Since there is no (or at least very little) friction in the vacuum of space, the object does not slow.... It simply continues.
Sattelites in "low" earth orbit do encounter some friction from the very thin upper atmosphere, and they will eventually "decay".
:)