Kirchhoff’s second rule requires
$\text{emf}-\text{Ir}-{\text{IR}}_{1}-{\text{IR}}_{2}=0$ . Rearranged, this is
$\text{emf}=\text{Ir}+{\text{IR}}_{1}+{\text{IR}}_{2}$ , which means the emf equals the sum of the
$\text{IR}$ (voltage) drops in the loop.
Applying kirchhoff’s rules
By applying Kirchhoff’s rules, we generate equations that allow us to find the unknowns in circuits. The unknowns may be currents, emfs, or resistances. Each time a rule is applied, an equation is produced. If there are as many independent equations as unknowns, then the problem can be solved. There are two decisions you must make when applying Kirchhoff’s rules. These decisions determine the signs of various quantities in the equations you obtain from applying the rules.
When applying Kirchhoff’s first rule, the junction rule, you must label the current in each branch and decide in what direction it is going. For example, in
[link] ,
[link] , and
[link] , currents are labeled
${I}_{1}$ ,
${I}_{2}$ ,
${I}_{3}$ , and
$I$ , and arrows indicate their directions. There is no risk here, for if you choose the wrong direction, the current will be of the correct magnitude but negative.
When applying Kirchhoff’s second rule, the loop rule, you must identify a closed loop and decide in which direction to go around it, clockwise or counterclockwise. For example, in
[link] the loop was traversed in the same direction as the current (clockwise). Again, there is no risk; going around the circuit in the opposite direction reverses the sign of every term in the equation, which is like multiplying both sides of the equation by
$\mathrm{\u20131.}$
[link] and the following points will help you get the plus or minus signs right when applying the loop rule. Note that the resistors and emfs are traversed by going from a to b. In many circuits, it will be necessary to construct more than one loop. In traversing each loop, one needs to be consistent for the sign of the change in potential. (See
[link] .)
When a resistor is traversed in the same direction as the current, the change in potential is
$-\text{IR}$ . (See
[link] .)
When a resistor is traversed in the direction opposite to the current, the change in potential is
$+\text{IR}$ . (See
[link] .)
When an emf is traversed from
$\u2013$ to + (the same direction it moves positive charge), the change in potential is +emf. (See
[link] .)
When an emf is traversed from + to
$\u2013$ (opposite to the direction it moves positive charge), the change in potential is
$-$ emf. (See
[link] .)
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?