Physics, 31.01.2020 04:52 shainaanderson24

Is v directly proportional to i (from v=
or is v inversely proportional to i (from p=iv)
as you might see, i'm confused by the two. can you illustrate the difference between the two?

Answers: 1

Show answers

Answers

First of all, I is proportional V according to the Ohm's Law. R is merely a constant you need to obtain an equation. However, it is true that R changes with temperature and pressure, therefore Ohm's Law is only applicable in an invariable environment. Also this constant R is different for different materials.

So, do not get confused.

Ohm's law is not a universal law, please remember that as well. Some materials do not follow it and we call them non-ohmic conductors. I hope I helped! ^-^

Answer from: drcarver

This question relates to how electricity is transmitted on various NATIONAL GRIDS. AC is used, partly because it can be transformed using a transformer. To get the electricity or maybe I should say the electrical POWER from A 1000 miles to B, if it were transitted at 250 V then the actual CURRENT needed in the line would be very high. That would cause problems in the cables, one of which would be heating. So, the voltage is stepped up to say 2500 V and v possibly more. Then the current going down the transmission lines is less, but the power transmitted is the same. At the B station, the AC is transformed from the 2500V transmission voltage back down to the commercial/domestic voltage of 250V. Then the current required can be drawn, 'cos the power has "got there".

Answer from: Quest

Less force and energy was applied

Answer from: Quest

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

$p(t)=0.3t^2+6t+80$

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

$p(0)=0+0+80=80$

according to question, we have said that if the population has twice its initial population, then it becomes

$p(t)=2\times 80=160$

so, time taken to reach this above mentioned population is given by

$160=0.3t^2+6t+80\\\\160-80=0.3t^2+6t\\\\80=0.3t^2+6t\\\\0.3t^2+6t-80=0\\\\\text{using quadratic formula ,we get }\\\\t_{1,\: 2}=\frac{-60\pm \sqrt{60^2-4\cdot \: 3\cdot \: 800}}{2\cdot \: 3}\\\\t=-29.14\ and\ t=9.149$

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

Another question on Physics

Physics, 22.06.2019 09:00

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy

Answers: 2

Answer

Physics, 22.06.2019 17:20

In a system with only a single force acting upon a body, what is the relationship between the change in kinetic energy and the work done by the force? answers: work is equal to the change in kinetic energy.work depends on the square of the change in potential energy.work is equal to the negative of the change in kinetic energy.work is equal to the square of the change in kinetic energy

Answers: 2

Answer

Physics, 22.06.2019 19:00

On average 8 bananas make up one pound. the price is four pounds for 5.00. you must buy 25 bananas.what is your cost?

Answers: 1

Answer

Physics, 22.06.2019 19:30

Refrigerant-134a flows through a carnot heat pump cycle at 0.5 kg/s. it is known that the maximum absolute temperature in the cycle is 1.1 times the minimum absolute temperature, and the net power input to the cycle is 2.5 kw. if the refrigerant changes from a saturated vapor to a saturated liquid during the heat rejection process, determine the maximum magnitude of the enthalpy of vaporization for this process in kj/kg (with 3 significant figures).

Answers: 3

Answer

You know the right answer?

Is v directly proportional to i (from v=
or is v inversely proportional to i (from p=iv)
...

Questions