Electricity Circuit - Question

[BAH0003]

Homework Statement

Hi,

I was just wondering how we would do one of these styled questions for certain aspects that we are looking for. I have attached a picture of a diagram of a circuit as well as the things that need to be found from it. If someone can break down the process and the answers for these, that would be great.

1) The voltage for each part when 4, 8 and 12 volts are supplied individually.
2) The current for each part when 4, 8 and 12 volts are supplied individually.
3) The equivalent effective resistance in arrangements in series
4) The equivalent effective resistance in arrangements in parallel
5) The resistance as the potential difference to current ratio.

I have attached a picture of the circuit in the "Attempt at a solution" part, if someone could help me as soon as possible that would be great.

Thanks

Relevant Equations

1/2+1/5=7/10=10/7=1.428571429
10 + 10 + 1.428571429 = 21.428571429
4/21..... = 0.19
8/21..... = 0.37
12/21... = 0.56

 

[BvU]

Hello Bah, ##\qquad## ##\qquad## !

You really made a bit of a mess of the template: relevant equations are equations, not an attempt at solution.

And a diagram in this case is more part of the problem statement than of the solution.

But some of the ingredients are present, so I'll try to untangle things and help:

1/2+1/5=7/10=10/7=1.428571429
10 + 10 + 1.428571429 = 21.428571429
4/21... = 0.19
8/21... = 0.37
12/21... = 0.56

In line 1 you calculate the effective resistance of the 2 ##\Omega## and 5 ##\Omega## in parallel. Using an equation like ##{1\over R_{parr}} = {1\over R_1} + {1\over R_2}##.

I strongly advise you not to write things like 7/10=10/7 because they are not true and will bite you at some point.
I also strongly advise you to add the proper units -- it will eventually help you make less errors.

Don't write down 11 digits if all you are given is two: restrict it to 1.43 ##\Omega## at most.In line 2 you calculate the effecive resitance of the series circuit of 10 ##\Omega##, the parallel effective R and the other 10 ##\Omega##. Don't write down 11 digits if all you are given is two: restrict it to 21.43 ##\Omega## at most.In line 3-5 you use Ohm's law to calculate the current in the three scenarios.

I was just wondering how we would do one of these styled questions for certain aspects that we are looking for

This leaves me wondering what it is you are asking ...

You answered 3), 4) and 5) yourself.

You do the right things using a sort of sloppy steno. I have the impression you know what to do. How can we help specifically ?

 

[BAH0003]

Hello Bah, ##\qquad## ##\qquad## !

You really made a bit of a mess of the template: relevant equations are equations, not an attempt at solution.

And a diagram in this case is more part of the problem statement than of the solution.

But some of the ingredients are present, so I'll try to untangle things and help:

In line 1 you calculate the effective resistance of the 2 ##\Omega## and 5 ##\Omega## in parallel. Using an equation like ##{1\over R_{parr}} = {1\over R_1} + {1\over R_2}##.

I strongly advise you not to write things like 7/10=10/7 because they are not true and will bite you at some point.
I also strongly advise you to add the proper units -- it will eventually help you make less errors.

Don't write down 11 digits if all you are given is two: restrict it to 1.43 ##\Omega## at most.In line 2 you calculate the effecive resitance of the series circuit of 10 ##\Omega##, the parallel effective R and the other 10 ##\Omega##. Don't write down 11 digits if all you are given is two: restrict it to 21.43 ##\Omega## at most.In line 3-5 you use Ohm's law to calculate the current in the three scenarios.

This leaves me wondering what it is you are asking ...

You answered 3), 4) and 5) yourself.

You do the right things using a sort of sloppy steno. I have the impression you know what to do. How can we help specifically ?

Hi,

Thanks for the feedback. I am more confident with 1) and 2), but need help how 3,4 and 5 would be done with relevant working out.

Thanks

 

[gneill]

1) The voltage for each part when 4, 8 and 12 volts are supplied individually.
2) The current for each part when 4, 8 and 12 volts are supplied individually.

It is not entirely clear what is being asked for here; the phrasing "for each part" could be interpreted to refer to the potential across, and the current through, each individual component of the circuit.

Is the problem statement exactly as it was given to you?

 

[BAH0003]

It is not entirely clear what is being asked for here; the phrasing "for each part" could be interpreted to refer to the potential across, and the current through, each individual component of the circuit.

Is the problem statement exactly as it was given to you?

No, it said to find the current and voltage for each resistor when 4V, 8V and 12V are supplied respectively. Do you know how this can be done?

 

[gneill]

No, it said to find the current and voltage for each resistor when 4V, 8V and 12V are supplied respectively. Do you know how this can be done?

Perhaps you should post the wording of the problem exactly as it was given to you so that we don't work on assumptions that may be incorrect.

Finding the potentials and currents is a matter of applying Kirchhoff's and Ohm's laws, which you should have covered in class. They should be your "Relevant Equations".