Answer:
![\rho=1.8\times 10^{-8}\Omega.m](https://tex.z-dn.net/?f=%5Crho%3D1.8%5Ctimes%2010%5E%7B-8%7D%5COmega.m)
Explanation:
Given:
width of the wire, ![w=1.8\ mm=1.8\times 10^{-3}\ m](https://tex.z-dn.net/?f=w%3D1.8%5C%20mm%3D1.8%5Ctimes%2010%5E%7B-3%7D%5C%20m)
thickness of the flat wire, ![d=0.12\ mm=1.2\times 10^{-4}](https://tex.z-dn.net/?f=d%3D0.12%5C%20mm%3D1.2%5Ctimes%2010%5E%7B-4%7D)
length of the wire, ![l=12\ m](https://tex.z-dn.net/?f=l%3D12%5C%20m)
voltage across the wire, ![V=12\ V](https://tex.z-dn.net/?f=V%3D12%5C%20V)
current through the wire, ![I=12\ A](https://tex.z-dn.net/?f=I%3D12%5C%20A)
Now the net resistance of the wire:
using ohm's law
![R=\frac{V}{I}](https://tex.z-dn.net/?f=R%3D%5Cfrac%7BV%7D%7BI%7D)
![R=\frac{12}{12}](https://tex.z-dn.net/?f=R%3D%5Cfrac%7B12%7D%7B12%7D)
![R=1\ \Omega](https://tex.z-dn.net/?f=R%3D1%5C%20%5COmega)
We have the relation between the resistivity and the resistance as:
![R=\rho.\frac{l}{a}](https://tex.z-dn.net/?f=R%3D%5Crho.%5Cfrac%7Bl%7D%7Ba%7D)
where:
a = cross sectional area of the wire
resistivity of the wire material
![1=\rho\times \frac{12}{1.8\times 10^{-3}\times 1.2\times 10^{-4}}](https://tex.z-dn.net/?f=1%3D%5Crho%5Ctimes%20%5Cfrac%7B12%7D%7B1.8%5Ctimes%2010%5E%7B-3%7D%5Ctimes%201.2%5Ctimes%2010%5E%7B-4%7D%7D)
![\rho=1.8\times 10^{-8}\Omega.m](https://tex.z-dn.net/?f=%5Crho%3D1.8%5Ctimes%2010%5E%7B-8%7D%5COmega.m)
Diagnosing illnesses: Radio Waves
Warming and cooking food: microwaves
Transmitting data from remote controls to televisions: infrared waves
Answer:
The magnetic field is
T
Explanation:
Given:
Velocity of electron ![v = 5 \times 10^{7} \frac{m}{s}](https://tex.z-dn.net/?f=v%20%3D%205%20%5Ctimes%2010%5E%7B7%7D%20%5Cfrac%7Bm%7D%7Bs%7D)
Electric field ![E = 10^{4} \frac{V}{m}](https://tex.z-dn.net/?f=E%20%3D%2010%5E%7B4%7D%20%5Cfrac%7BV%7D%7Bm%7D)
The force on electron in magnetic field is given by,
......(1)
The force on electron in electric field is given by,
......(2)
Compare both equation,
![qE = qvB \sin \theta](https://tex.z-dn.net/?f=qE%20%3D%20qvB%20%5Csin%20%5Ctheta)
Here ![\sin \theta = 1](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%20%3D%201)
![E = vB](https://tex.z-dn.net/?f=E%20%3D%20vB)
![B= \frac{E}{v}](https://tex.z-dn.net/?f=B%3D%20%5Cfrac%7BE%7D%7Bv%7D)
![B = \frac{10^{4} }{5 \times 10^{7} }](https://tex.z-dn.net/?f=B%20%3D%20%5Cfrac%7B10%5E%7B4%7D%20%7D%7B5%20%5Ctimes%2010%5E%7B7%7D%20%7D)
T
Therefore, the magnetic field is
T
What is the variable?
~<em>the</em><em> </em><em>price</em><em> </em><em>is</em><em> </em><em>the</em><em> </em><em>variable</em><em>.</em>
What happens to demand?
~It'll go down. Since the price of snow blowers will increase then the quantity demanded will go down.
Hope this helps- have a good day bro cya)