We know that the Delta E + W(Work done by non-conservative
forces) = 0 (change of energy)
In here, the non-conservative force is the friction force
where f = uN (u =kinetic friction coefficient)
W= f x d = uNd ; N=mg
Delta E = 1/2 mV^2 -1/2mVi^2
umgd + 1/2mV^2 - 1/2mVi^2 = 0 (cancel out the m term)
This will then give us:
1/2Vi^2-ugd = 1/2V^2
V^2 = Vi^2 - 2ugd
So plugging in our values, will give us:
V= Sqrt (5.6^2 -2.3^2)
=sqrt (26.07)
= 5.11 m/s
You can see what is the electron configuration by looking at the layout of the periodic tables. the first shell will have a max of 2 electrons on it, once the first one is filled up a second is added with a max of 8 electrons on it and so on with the 8 as a max. so He, and H will only have them on the first shell but every horizontal row is a new valence or outer shell. so lets say for carbon look at the number in the upper left corner of the box will tell you the total number of electrons you will need. so start off with the first two electrons on the first shell. now you know that carbon needs 6 electrons in total, since you can only have a max of 2 on the first shell you need a second one so on the second one you will have to have the remaining 4. now elements are most stable when they have a full valence shell becuase those are the only electrons that will react with others. so if carbon has 4 it wants to either gain or lose 4 electrons so you could say that it would bond with 4H since each H will donate 1 electron to the C valence shell making all the H and C stable. CH4(methane)
Let's see: frequency of cellular phone waves (GSM phones) is (800-1900 MHz). If we look at the table of the electromagnetic spectrum, we can see that this range is contained within the frequencies of the microwaves, which include waves in the range 300 MHz-300 GHz.
So, summarizing, the correct answer is "microwaves".
Answer:
12 (Magnesium- Mg)
Explanation:
Looking at the four numbers, we have:
Magnesium, Silicon, Sulfur, and Chlorine.
We can eliminate two of the answers immediately just by looking at the periodic table.
Sulfur and Chlorine are on the nonmetal side of the periodic table. So that's <em>definitely</em> not it. That leaves Magnesium and Silicon.
Silicon is a Metalloid. Magnesium is an Alkaline earth Metal.
Metaloids are elements that have a mix of both<em> metal</em> and<em> nonmetal </em>properties (luster, how it feels, etc.). Since it's a MIX and Magnesium is just straight METAL-
We can say Magnesium has the most metallic properties.
hope this helps!!
Answer:
the velocity is 10 m/s
Explanation:
Using the expression for kinetic energy we have:
![Ek=\frac{1}{2} *m*v^{2} \\\\Ek=100J\\m=2kg\\v=\sqrt{(2*100/2)}\\ v=10[m/s]](https://tex.z-dn.net/?f=Ek%3D%5Cfrac%7B1%7D%7B2%7D%20%2Am%2Av%5E%7B2%7D%20%5C%5C%5C%5CEk%3D100J%5C%5Cm%3D2kg%5C%5Cv%3D%5Csqrt%7B%282%2A100%2F2%29%7D%5C%5C%20v%3D10%5Bm%2Fs%5D)