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.
Answer:
C. The car from driving off the road on a curve
Explanation:
A centripetal force actually causes circular motion. This occurs when an object moves in a circular path or a circle,a force will definitely act on it.
For instance, a car travelling in a circular path must definitely experience this force acting on it, even when the car moves at a constant speed. If it does not exist the object will definitely spin off in a direction tangential to the circular path or curve.
Because even though the object got crush and misshape it still has the same identity. the identity never change
Answer:
The chance in distance is 25 knots
Explanation:
The distance between the two particles is given by:
(1)
Since A is traveling north and B is traveling east we can say that their displacement vector are perpendicular and therefore (1) transformed as:
(2)
Taking the differential with respect to time:
(3)
where 
and 
are the respective given velocities of the boats. To find 
and 
we make use of the given position for A, 
, the Pythagoras theorem and the relation between distance and velocity for a movement with constant velocity.
with this time, we know can now calculate the distance at which B is:
and applying Pythagoras:
Now substituting all the values in (3) and solving for 
we get:
