Yes. The noble gases are just a specific type of non metals. Such as the halogens.
Answer:
1.424 μC
Explanation:
I'm assuming here, that the charged ball is suspended by the string. If the string also is deflected by the angle α, then the forces acting on it would be: mg (acting downwards),
tension T (acting along the string - to the pivot point), and
F (electric force – acting along the line connecting the charges).
We then have something like this
x: T•sin α = F,
y: T•cosα = mg.
Dividing the first one by the second one we have
T•sin α/ T•cosα = F/mg, ultimately,
tan α = F/mg.
Since we already know that
q1=q2=q, and
r=2•L•sinα,
k=9•10^9 N•m²/C²
Remember,
F =k•q1•q2/r², if we substitute for r, we have
F = k•q²/(2•L•sinα)².
tan α = F/mg =
= k•q²/(2•L•sinα)² •mg.
q = (2•L•sinα) • √(m•g•tanα/k)=
=(2•0.5•0.486) • √(0.0142•9.8•0.557/9•10^9) =
q = 0.486 • √(8.61•10^-12)
q = 0.486 • 2.93•10^-6
q = 1.424•10^-6 C
q = 1.424 μC.
It is letter b which is Global Warming
Answer:
Explanation:
So we want the speed to go from 25 m/s to 0 m/s in 170 m, but the time needs to incorporate the reaction time, so the slowing down will not start until .68 s pass. Or, in other words, the train will travel an extra 25 m/s * .68 s = 17 m. This means, instead of 170 m to slow down it has 153. Hopefully that makes sense. With this information we can use the equation vf^2-vi^2=2ad. If that equation is unfamiliar you need to get a better handle on your physics equations.
Anyway, let's plug in.
vf = 0 m/s
vi = 25 m/s
a is what we're trying to find
d = 153 m
vf^2-vi^2=2ad
a = (vf^2-vi^2)/(2d)
Can you handle figuring it out from there? or if there is something you don't understand let me know.
The object is white, A. White has no color because it reflects all light, which is also why wearing white makes you cooler than wearing black. Because black absorbs all light.