Answer:
The temperature of silver at this given resistivity is 2971.1 ⁰C
Explanation:
The resistivity of silver is calculated as follows;
![R_t = R_o[1 + \alpha(T-T_o)]\\\\](https://tex.z-dn.net/?f=R_t%20%3D%20R_o%5B1%20%2B%20%5Calpha%28T-T_o%29%5D%5C%5C%5C%5C)
where;
Rt is the resistivity of silver at the given temperature
Ro is the resistivity of silver at room temperature
α is the temperature coefficient of resistance
To is the room temperature
T is the temperature at which the resistivity of silver will be two times the resistivity of iron at room temperature
![R_t = R_o[1 + \alpha(T-T_o)]\\\\\R_t = 1.59*10^{-8}[1 + 0.0038(T-20)]](https://tex.z-dn.net/?f=R_t%20%3D%20R_o%5B1%20%2B%20%5Calpha%28T-T_o%29%5D%5C%5C%5C%5C%5CR_t%20%3D%201.59%2A10%5E%7B-8%7D%5B1%20%2B%200.0038%28T-20%29%5D)
Resistivity of iron at room temperature = 9.71 x 10⁻⁸ ohm.m
When silver's resistivity becomes 2 times the resistivity of iron, we will have the following equations;
![R_t,_{silver} = 2R_o,_{iron}\\\\1.59*10^{-8}[1 + 0.0038(T-20)] =(2 *9.71*10^{-8})\\\\\ \ (divide \ through \ by \ 1.59*10^{-8})\\\\1 + 0.0038(T-20) = 12.214\\\\1 + 0.0038T - 0.076 = 12.214\\\\0.0038T +0.924 = 12.214\\\\0.0038T = 12.214 - 0.924\\\\0.0038T = 11.29\\\\T = \frac{11.29}{0.0038} \\\\T = 2971.1 \ ^0C](https://tex.z-dn.net/?f=R_t%2C_%7Bsilver%7D%20%3D%202R_o%2C_%7Biron%7D%5C%5C%5C%5C1.59%2A10%5E%7B-8%7D%5B1%20%2B%200.0038%28T-20%29%5D%20%3D%282%20%2A9.71%2A10%5E%7B-8%7D%29%5C%5C%5C%5C%5C%20%5C%20%28divide%20%5C%20through%20%5C%20by%20%5C%201.59%2A10%5E%7B-8%7D%29%5C%5C%5C%5C1%20%2B%200.0038%28T-20%29%20%3D%2012.214%5C%5C%5C%5C1%20%2B%200.0038T%20-%200.076%20%3D%2012.214%5C%5C%5C%5C0.0038T%20%2B0.924%20%3D%2012.214%5C%5C%5C%5C0.0038T%20%20%3D%2012.214%20-%200.924%5C%5C%5C%5C0.0038T%20%3D%2011.29%5C%5C%5C%5CT%20%3D%20%5Cfrac%7B11.29%7D%7B0.0038%7D%20%5C%5C%5C%5CT%20%3D%202971.1%20%5C%20%5E0C)
Therefore, the temperature of silver at this given resistivity is 2971.1 ⁰C
Answer:
B) 2I
Explanation:
The equation that relates voltage, current and resistance is V=RI.
The equation for the resistance of a material in terms of its resistivity, length and cross-sectional area is 
In this case, the length is divided by 2 while keeping its resistivity (since it's the same material) and area, which means the resistance gets divided by 2. Then, looking at the equation I=V/R and keeping V constant, one deduces that since the resistance now is half than before then current now must be twice as before.
This is all intuitive in fact, cuting a homogeneous resistor in half and leaving the rest of the variables constant makes twice as easy for the electrons to cross the conductor, thus twice the current (one has to know that all the variables involved behave linearly, as the equations show).
Answer:
Liquid has a defined volume but undefined shape
Explanation:
Explanation:
Solid has specific shape and volume
Liquid has specific volume but no specific shape
Gases have no specific volume and no specific shape
So correct answer is liquid.
Newton's third law states "for every action, there is an equal and opposite reaction."
What this is pretty much saying is that for every action, there is a consequence. One force connects and triggers another.
