Answer:
Diameter of wire B is 2 times the diameter of wire A
Explanation:
We have given two wire A and B
They are made up of same material and length of both the wire is sane
So 
Let the resistivity of both the wire is 
It is given that wire A has 4 times the resistance as wire B
So 
So
( As
)




So diameter of wire B is 2 times the diameter of wire A
Answer:

Explanation:
Let the distance from spotlight to wall be 15m, and distance from the man to the building be
.
#Therefore the height of the shadow as a function of the above is 
Hence, height of the shadow is expressed as s=(15-x)m
#See attached photo for illustration
Heya!!
For calculate aceleration, lets applicate second law of Newton:

<u>Δ Being Δ</u>
F = Force = 78,3 N
m = Mass = 24,5 kg
a = Aceleration = ?
⇒ Let's replace according the formula and clear "a":

⇒ Resolving

Result:
The aceleration is <u>3,19 meters per second squared (m/s²)</u>
Good Luck!!
Answer:
Hi
before I answer a question I think very deeply and try my best, hope it helps...
As you know there are many different types of systems. For example, The solar system, galaxies, quantum systems, atoms, molecules, orchestras, nervous system, etc, things you may not have even considered a system. To get to the basis of a system we must first understand what a system is then we will show some examples. A system is a group of Parts (parts could mean anything even dark energy and dark matter) that work together to accomplish something. For example, your body has many many trillions of cells that all try to accomplish the functions of humans which include thinking, moving, breathing, circulation, etc. Cells in turn are a system that have counterparts called organelles that accomplish harvesting energy, making new proteins, getting rid of waste, and so on. These are some systems which we highly dependent upon.
Well i hope it helped
Spiky Bob your answerer
Ok, I think this is right but I am not sure:
Q = ϵ
0AE
A= π π
r^2
=(8.85x10^-12 C^2/Nm^2)
( π π (0.02m)^2)
(3x10^6 N/C) =3.3x10^-8 C = 33nC N = Q/e = (3.3x10^-8 C)/(1.60x10^-19 C/electron) = 2.1x10^11 electrons