Answer:. Option c
Explanation: the speed of an electromagnetic wave is simply the vector product of the magnetic field and the electric field.
The direction of the velocity is the direction of the electromagnetic wave.
The wave is already moving towards the negative y axis (-j) and the magnetic field is already pointing towards the positive x axis (i)
From cross product of unit vectors
i × j = k
i × k = - j
With the second identity, we can see that the electric field will be pointing towards the positive of the x axis (k).
Option c is validated
Gravitational force is very weaker;
Answer: Part A the right sentence is: Because the proton is a positive charge and it slows down as it travels, it must be moving from a region of lower potential to a region of higher potential
Part B. aproximatelly 98 times ΔV V
Part C. the initial kinetic energy of the proton is 1.87 10^3 eV
Explanation: Part A. The field stops the proton so the lines of electric fild must be directed in opposite direction of its movement. This means that the proton moves to a higher potential. Part B The kinetic energy of the is transformed in electric potenctial for the proton.
Part C. Energy in J divide the charge of electron gives the energy in eV.
C. The daughters received a random set of genes from both of their parents
Different densities have to have a reason - different pressure and/or humidity etc. If there is a different pressure, there is a mechanical force that preserves the pressure difference: think about the cyclones that have a lower pressure in the center. The cyclones rotate in the right direction and the cyclone may be preserved by the Coriolis force.
If the two air masses differ by humidity, the mixing will almost always lead to precipitation - which includes a phase transition for water etc. It's because the vapor from the more humid air mass gets condensed under the conditions of the other. You get some rain. In general, intense precipitation, thunderstorms, and other visible isolated weather events are linked to weather fronts.
At any rate, a mixing of two air masses is a nontrivial, violent process in general. That's why the boundary is called a "front". In the military jargon, a front is the contested frontier of a conflict. So your idea that the air masses could mix quickly and peacefully - whatever you exactly mean quantitatively - either neglects the inertia of the air, a relatively low diffusion coefficient, a low thermal conductivity, and/or high latent heat of water vapor. A front is something that didn't disappear within minutes so pretty much tautologically, there must be forces that make such a quick disappearance impossible.
