The only way to truly test if a variable is undefined is to do the following. Remember, undefined is an object in Javascript. To determine if a variable or object property exists, It is good to compare to keyword undefined or you can also check the type of the object to string âundefinedâ. In the following JavaScript code we compare the num to the undefined in both way.
Nuclear waste -- The waste from nuclear power plants will be toxic for humans for more than 100,000 years. Itâs untenable now to secure and store all of the waste from the plants that exist. To scale up to 2,500 or 3,000, let alone 17,000 plants is unthinkable.
In this article, we'll explain how nuclear reactors work, what happens when they malfunction, and the risks they pose to our health and the environment compared to other energy sources. We'll also take a look at what technological advances could make the nuclear reactors of the future safer. But first, let's look at how nuclear fission, the process that actually produces the energy, actually works.