Answer:
The correct answer is 
Explanation:
The formula for the electron drift speed is given as follows,
where n is the number of of electrons per unit m³, q is the charge on an electron and A is the cross-sectional area of the copper wire and I is the current. We see that we already have A , q and I. The only thing left to calculate is the electron density n that is the number of electrons per unit volume.
Using the information provided in the question we can see that the number of moles of copper atoms in a cm³ of volume of the conductor is 
. Converting this number to m³ using very elementary unit conversion we get 
. If we multiply this number by the Avagardo number which is the number of atoms per mol of any gas , we get the number of atoms per m³ which in this case is equal to the number of electron per m³ because one electron per atom of copper contribute to the current. So we get,
if we convert the area from mm³ to m³ we get 
.So now that we have n, we plug in all the values of A ,I ,q and n into the main equation to obtain,
which is our final answer.
Answer:
a
b
Explanation:
From the question we are told that
The pressure of the water in the pipe is 
The speed of the water is 
The original area of the pipe is 
The new area of the pipe is ![A_2 = \pi * \frac{[\frac{d}{2} ]^2}{4} = \pi * \frac{\frac{d^2}{4} }{4} = \pi \frac{d^2}{16}](https://tex.z-dn.net/?f=A_2%20%3D%20%5Cpi%20%2A%20%20%5Cfrac%7B%5B%5Cfrac%7Bd%7D%7B2%7D%20%5D%5E2%7D%7B4%7D%20%20%3D%20%20%5Cpi%20%2A%20%20%5Cfrac%7B%5Cfrac%7Bd%5E2%7D%7B4%7D%20%7D%7B4%7D%20%3D%20%5Cpi%20%5Cfrac%7Bd%5E2%7D%7B16%7D)
Generally the continuity equation is mathematically represented as
Here 
is the new velocity
So
=> 
=> 
=> 
=>
Generally given that the height of the original pipe and the narrower pipe are the same , then we will b making use of the Bernoulli's equation for constant height to calculate the pressure
This is mathematically represented as
Here 
is the density of water with value 
![P_2 = P_1 + \frac{1}{2} * \rho [ v_1^2 - v_2^2 ]](https://tex.z-dn.net/?f=P_2%20%3D%20%20P_1%20%2B%20%5Cfrac%7B1%7D%7B2%7D%20%2A%20%20%5Crho%20%5B%20v_1%5E2%20-%20v_2%5E2%20%5D)
=> ![P_2 = 110 *10^{3} + \frac{1}{2} * 1000 * [ 1.4 ^2 - 5.6 ^2 ]](https://tex.z-dn.net/?f=P_2%20%3D%20%20110%20%2A10%5E%7B3%7D%20%2B%20%5Cfrac%7B1%7D%7B2%7D%20%2A%20%201000%20%2A%20%20%5B%201.4%20%5E2%20-%205.6%20%5E2%20%5D)
=>
They should look for <span>a report from an independent scientific research firm,
even if they have to pay for it.
In preparing its report, the firm would have already surveyed many of the </span>
<span>citizens from several other towns that currently add fluoride to their water,
plus a lot of other relevant medical research on the subject.</span>
Answer:
Flip the cell.
Explanation:
This reverses direction of energy transfer.
Alternatively, flip ammeters and voltmeters to give negative readings.
what do penguins eat for lunch?
Ice-burgers!
