Answer:
Efficiency of a machine is how well the machine works and what the machine is capable of doing.
Mechanical advantage=Load/Effort.
720/180=4
Answer:
the oscillations of the electrons must be in the 10⁸ Hz = 100 MHz range
Explanation:
The speed of a wave of radio, television, light, heat, all are manifestations of electromagnetic waves that are oscillations of electric and magnetic fields that support each other, the speed of all these waves is the same and the vacuum is equal to c = 3 108 m / s
All waves have a relationship between the speed of the wave, its frequency and wavelength
c = λ f
f = c /λ
for this case lam = 1 m
f = 3 10⁸/1
f = 3 10⁸ Hz
the oscillations of the electrons must be in the MHz range
It should be clarified that the speed of light in air is a little lower
n = c / v
v = c / n
the refractive index of vacuum is n = 1 and the refractive index of air is n = 1.000002
Answer:
B. the stars to come back to the same positions in the sky.
Explanation:
In fact, the solar day is equivalent to more than a rotation, because when the point has turned completely, it is not, as it should, in the same position with respect to the Sun.
The reason for this is that while performing the rotation, the Earth simultaneously moved following its orbit around the Sun.
When the reference point completed its rotation, the Earth already moved almost 2,500,000 km., So that to see the Sun again it will be necessary to turn a little more.
Solar day is more than a rotation. The sidereal or sidereal day, commonly used by astronomers, is also based on the rotation of the Earth; but in this case a distant star is taken as a reference (sidereal comes from the Latin sidus which means "star").
Molecules of liquid are far away from each other but less compared to gas. Liquid has the ability to flow. Liquid molecules can move. Liquid occupies the shape of the container. Thus, they do not have fixed shape. Liquid has fixed volume because they are not compressible(easily)
the answer is true because they're so close together that they can't move they can't slide past each other or anything
