<span>Tectonic plates move because they are floating on top of the liquid mantle. The mantle itself moves due to convection currents: hot rock rises, gives off some heat, then falls. This creates vast swirls of moving liquid rock under the crust of the earth, which jostles the plates of crust on top.
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Answer:
λ = 5.65m
Explanation:
The Path Difference Condition is given as:
δ=
;
where lamda is represent by the symbol (λ) and is the wavelength we are meant to calculate.
m = no of openings which is 2
∴δ= 
n is the index of refraction of the medium in which the wave is traveling
To find δ we have;
δ= 
δ= 
δ= 
δ= 
δ= 
δ= 
δ= 82.15 -73.68
δ= 8.47
Again remember; to calculate the wavelength of the ocean waves; we have:
δ= 
δ= 8.47
8.47 = 
λ = 
λ = 5.65m
There is no theoretical OR observational evidence for that statement.
Explanation :
It is given that, q and 4q are placed at a distance of l.
Let x is the distance where third charge is placed so that the entire three charge system is in static equilibrium.
Equilibrium means the net force acting on the system of charges is equal to zero. Let Q is the third charge.
So, 
On solving,

For magnitude :

using 

So, a charge of -4q/9 is at a distance of l/3 is placed. It is placed to the right of +q.