V=d/t
V=?
d=400m(4)
=1600m
t=6 min.
=360 s
V=1600m/360s
V=4.4m/s
Answer: A, C and D
Explanation:
Interference occurs when two waves superimpose to form a wave having a smaller or larger amplitude.
Constructive interference is said to occur when two waves superimpose to produce a wave having larger amplitude. It occurs for the waves having phase difference of multiple of 2π. On the other hand, destructive interference occurs for the waves having phase difference π, 3π, ..and so on.
In the given picture, the bright regions represent constructive interference where as the dark ones between them represent destructive interference. Thus, the correct letters representing constructive interference are: A, C and D.
Answer:
d) 0 V
Explanation:
It can be showed that the potential due to a point charge q, to a distance d from the charge, can be expressed as follows:
where k = 
As the potential is an scalar, and is linear with the charge, we can apply the superposition principle, which means that we can find the potential due to one of the charges, as if the other were not present.
By symmetry, all four charges are at the same distance from the center, so we can write the total potential, as follows:
where d, is the semi-diagonal of the square, that we can find applying Pythagorean theorem, as follows:
Replacing by the values in (1) we have:
which is equal to the option d).
Answer:
Explanation:
a) Magnification = image height / object height = -9 / 18 = -0.5
b) Magnification = - image distance / object distance = -0.5
so image distance = 0.5 object distance
1/focal length = 1/image distance + 1/object distance
1/6 = 1/(0.5 object distance) + 1/object distance
object distance = 18.0 cm
c) Image appears behind the lens.
Answer:
Lubrication
Explanation:
People oil/lubricate bicycle chains because the chain turns around the cogs and rub together so this help with friction.
Hope this helps :)
