The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
The correct answer for the question that is being presented above is this one: "a. Constructive interference." The kind of process that can create "rogue" waves is constructive interference. Constructive interference refers to <span>the </span>interference<span> of two or more waves of equal frequency and phase creating a mutual one.</span>
Answer: Use the formula q = m·ΔHv in which q = heat energy, m = mass, and ΔHv = heat of vaporization.