The ohm (symbol: Ω) is the SI derived unit of electrical resistance, named after German physicist Georg Ohm. Various empirically derived standard units for electrical resistance were developed in connection with early telegraphy practice, and the British Association for the Advancement of Science proposed a unit derived from existing units of mass, length and time, and of a convenient scale for practical work as early as 1861. As of 2020, the definition of the ohm is expressed in terms of the quantum Hall effect.
Homework Statement
Given I = Io (exp (V/Vo) -1), Io = 1 A, Vo = 1 V, R = 1 ohm
(i) Find R when V = 5 Volt
(ii) Find R when V = 10 Volt
(iii) Plot the graph of V vs I
(iv) Explain why the Ohm’s law can’t be applied
Homework Equations
V = I*R
The Attempt at a Solution
(i)...
how do i go about answering this question guys, send me in the right direction please :)
"when a diode allows a positive current to flow it has a resistance of 0.5kohms. It does not allow negative flow, i.e. the resistance is infinate. using ohms law, sketch a graph of current I against...
Homework Statement
Suppose you wish to fabricate a uniform wire out of 2.1 grams of copper. If the wire is to have a resistance of 0.3 ohms and if all of the copper is to be used, what must the diameter of this wire (in mm) be?
Homework Equations
mass (in kg), cross-sectional area...
Hi all, I want to use a 0 ohm resistor for single-point grounding to connect analog/digital ground together. Since the current could be pretty large (several hundred mAs), I'm considering how to choose the resistor for its power consumption. Yes it's "0 ohm", which makes it seem that any size...
Homework Statement
A 0.25 UF capacitor is charged to 50 V. It is then connected in series with a 25 ohm resistor and a 100 ohm resistor and allowed to discharge completely.
Homework Equations
P=I V=I^2R=(V^2)/R
The Attempt at a Solution
i'm not sure how to approach this problem. it...
A 10 ohm resistor in a series with a bulb and a 12v source.
a) If the 8.0V is across the bulb, what is the voltage across the resistor?
I wrote 4v, is this correct?
b) What is the current in the circuit? I wrote 1.5A, is this correct?
c) What is the resistence of the bulb? Could...
Homework Statement
What is the time constant of a 2mh inductor and a 200 ohm resistor connected in series?
Homework Equations
The Attempt at a Solution
I'm having a tough time wrapping my head around something that seems so simple. The Question is:
What is the maximum output power from a 12 volt battery that has an internal resistance of 6 ohm ?
The answer from this books is 6 W?
My formula
First I need to find the current
I = V/R...
Tolerance rating on a 0 Ohm resistor?
I'm just curious why the zero ohm "jumper" resistors I use have a tolerance rating of 5%. This doesn't really make sense to me because 5% of 0 Ohms is still 0 Ohms. I understand that even a close to ideal conductor is not going to be 0 Ohms, but why do...
Homework Statement
I need to calculate the replacement resistance Rv (Ohm) of the following
R1 = 12 ohm
R2 = 8 ohm
R3 = 6 ohm
R4 = 4 ohm
R5 = 9 ohm
R6 = 12 ohm
R7 = 4 ohm
I've been trying to include a picture that I've drawn in paint but apparently a couple of lines exceeds the...
Homework Statement
you measure a 20v potential difference across a 5 ohm resistor. what is the current?
The Attempt at a Solution
20 v/5 ohms = 4 v
is this correct? thanks.
im given a a 20-mH inductor and a 30 ohm resistor in parallel. Z_in is 25 degrees. and I am asked to find the frequency omega in rad/s here's what i try to do:
25=(jw.02*30)/(jw.02+30), and solve for w, but i don't get the right answer.
what is it that I am doing wrong?
im stuck on this question and was wondering if anyone could help point me in the right direction:
a half wave rectified voltage is described by: v(t)=100.sinX
(that X is mean to be theta)
when applied to a 50 ohm resistor find the average and rms values of the current.
thanks an help is...
Hi! I connect 9 volts to a 1 ohm resistor and thought I would get I = U/R = 9 A. But when I connect the ampmeter, I cannot read anything! Where is the problem?
This might be a silly one, but I'm a bit stumped:
Suppose you have a 6V battery and an unlimited supply of 1 ohm resistors.
How do you drop the potential from 6V to 4V using the resistors?
Off the top of my head I think you just put two of the resistors into a series attached to the...
Hello,
can you advise me how could you construct a 25 ohm resistance from a boz containing a dozen 10 ohm resistors?
can someone explain this in details...
i'm new to physics...
greatly appreciated! thanks again!
cseet
ok, so I'm a physics ignaramus. and a spelling one too.
but recently i was thinking about what is this thing we call music
and why, when u go to a jam concert (Grateful Dead, Phish, Etc.)- you reach something like a meditative state, (yes, even without drugs)
and i stumbled upon Ohm...