Light can be seen as an electromagnetic wave.
What happens when two waves, with the same frequency, superpose is called interference.
If at a certain point two waves arrive both with a crest, we have constructive interference and the amplitudes sum up, reaching the maximum value, resulting in bright spots.
If at a certain point one of the waves arrives with a crest and the other wave arrives with a trough, we have destructive interference, and the two amplitudes cancel out, resulting in dark spots.
Therefore, t<span>he dark bands on the wall are from destructive interference.</span>
Answer:
A
Explanation:
At constant speed, acceleration=0
From the formula, Fnet=ma (Resultant force= mass x acceleration), sub a=0
Fnet=0
Since the resultant force=0, the pushing force is equal to the frictional force
<span>D. Mass equals weight times acceleration due to gravity.
choose
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If an object has a density greater than the liquid in which it is placed it will sink.
Explanation:
Density of the object can be known by its mass and volume.
If two objects have same volume but different masses it means the one having more mass will have higher density. Density is amount of mass per unit volume.
Objects that are tightly packed have higher density.
According to Archimedes' principle when a body is fully immersed that an upward buoyant force is equal to weight of the fluid that object displaces.
Answer:
0.000314 Am²
6.049*10^-7 T
Explanation:
A
From the definitions of magnetic dipole moment, we can establish that
= , where
= the magnetic dipole moment in itself
= Current, 100 A
= Area, πr² (r = diameter divided by 2). Converting to m², we have 0.000001 m²
On solving, we have
= ,
= 100 * 3.14 * 0.000001
= 0.000314 Am²
B
=
(0)/4
* 2
/
³, where
(0) = constant of permeability = 1.256*10^-6
z = 4.7 cm = 0.047 m
B = 1.256*10^-6 / 4*3.142 * [2 * 0.000314/0.047³]
B = 1*10^-7 * 0.000628/1.038*10^-4
B = 1*10^-7 * 6.049
B = 6.049*10^-7 T