Answer:
D. because the light is reflected back into the fiber along its sides
Explanation:
The fiber is constructed in a way that the light is bent/reflected/refracted toward the center core of glass. So, from the center core, there is a layer above it that has a different propagation than the core, and above that the same thing. To give you a real world visual example, if you look down in a pool of water, then stick a straight stick into it, you see that the straight stick appears to bend. That is what is happening to the light as it travels through a different medium (air to water). This same effect is incorporated in the fiber optic cable construction.
We know that impulse is simply the product of Force and time:
Impulse = Force * time
Since Force has a unit of Newton or kg m/s^2 and time is in
seconds, therefore impulse can have units as:
N s
or
<span>kg m/s</span>
Choices 'a', 'c', and 'd' are true.
In choice 'b', I'm not sure what it means when it says that masses
are 'balanced'. To me, masses are only balanced when they're on
a see-saw, or on opposite ends of a rope that goes over a pulley.
Maybe the statement means that the mass of the nucleus and the
mass of the electron cloud are equal. This is way false. It takes
more than 1,800 electrons to make the mass of ONE proton or
neutron, and the most complex atom in nature only has 92 electrons
in it. So there's no way that the masses of the nucleus and the electrons
in one atom could ever be anywhere near equal.
Answer:
Option (D)
Explanation:
The velocity at which blood flows in the blood vessels is inversely proportional to the total cross-sectional area of the blood vessels present in the body. This means that if the cross sectional area of the vessels low, then there will be high rate of blood flow, and vice versa. This blood flow is minimum in the case of capillaries, where it gets enough time for the exchanging of essential nutrients as well as gases.
Thus, the correct answer is option (D).
The global warming is the uniform heating of the globe due to the effect of greenhouse gases.
Answer: Option B
<u>Explanation:</u>
Global warming is thus the theory that says that earth is warming up with an increase in temperature over time due to increment in the greenhouse gases.
These are greenhouse gases that are getting increased due to the human activity or say over exploitation of the natural resources. The heating of the globe has caused ozone layer depletion which is also causing warming.