Question

what does frequency and potential difference practically mean?!!!!!!!!

Answer 1

The frequency of something is how many cycles it goes through per a given amount of time, and the potential difference is the difference in potential energy per unit mass or charge, depending on the context.

Answer 2

thats the definition...(i know).....but practically....

Answer 3

frequency is practically derived from the word how frequent things are occurring so basically if take example of cycles repeated ...it means how often cycle is repeated in a given time period..now potential difference practically means the difference between the capability higher the difference higher will be capability...

Answer 4

Frequency is how often something occurs. Potential is energy that hasn't happened yet.

gravitational potential energy example:

mgh = PE, mass held at height h

If dropped, all it's PE will become KE
\[mgh = (1/2)mv^2\]

solve for v

\[v = \sqrt(2gh)\]

is the maximum speed it will go right before it hits the ground.

Answer 5

I think the original poster is clear on what frequency and potential is and his question is related their practical uses in electricity.

In a practical sense, higher voltages provide the ability to transmit large amounts of power through smaller cables (think high tension power lines). In addition, compare the sizes of motors which require 460V to ones that require 120V and you'll see that 460V motors will be smaller and lighter while providing the same horsepower. Power is directly proportional to current and voltage (P=IV). Therefore if the input voltage is higher, the current goes down and you can reduce the sizes of the components (sizes which are largely based on dissipating the heat produced by the current).

Frequency (alternating current) is the result of how motor-generators are made and is based on exactly two factors: the number of magnetic poles (P) the generator has and the speed of rotation (N). The formula is pretty straightforward:
\[f=\frac{PN}{120}\]Using that formula you'll see that a generator with 4 poles is required to run at 1800 rpm if the desired output frequency is 60hz.

At any rate, higher frequencies are generally used in systems that require more stable power, lightweight components and high reliability. As you can imagine, the aircraft/aerospace industries need this and as a result they commonly use 400hz AC. The generators which produce 400hz are significantly more expensive because they require higher quality wire & components. For the added cost however you can produce motors with 10 times the power for the same weight and size of a 60hz motor. So it's always a tradeoff between cost and performance.

I hope this helps.

Answer 6

On a clock: the second hand's frequency is 60 seconds, the minute hand's frequency is 60 minutes and the hour hand's frequency is 12 hours.

Answer 7

^ That's not true, frequency is measured in units of inverse time.....

Answer 8

thx btw

Answer 9

Sorry, I meant period.