Whats the formula for this question:-
A current of 4.5A flows in a3.5 W resistor for 5.5 minutes. The energy dissapated is?
Regards
Mick Ward
:confused::confused::confused:
what is the maximum permitted voltage drop of a cable supplied from 400v three phase.
a.11.5v
b.6.9v
c.20v
d.12v
I know the answers c but I dont know what the formula is to get there.
does anyone know
Hi
Can anybody remember the formula for working out ring main cable sizes (Cable Capacities). I know we use 32amp MCB with 2 x 2.5mm² but its been so long I cant remember the formula that proves 2.5mm² is capable of carrying a ring main load.
Thank you in advance
Sorry if this has been...
Hi there
Am studying 2330 level 3 and have come accross a formula I cant get my head round in my workbook. It shows the formula to calculate the difference in resistance with temperature change.
R1/R2 = (1 + alpha t1)/(1 + alpha t2)
The worked example shows a field winding of a dc motor with...
Just been doing some college work.
Was calculating if supp equip bonding was required in a bathroom. The formula given for an mcb is R < 50V / Ia.
Ia being the fault current for a particular mcb to disconnect in a certain time.
My question is, as there are likely to be various circuits in...
Morning everyone
Can't seem to get my head around this today:confused::confused:
Why is I squared in the formula P=I2xR and why is U squared in the formula P=U2/R
Many thanks
Mark
OK don't worry, LOL just had a short term memory loss:D.
Below is a list of links that i have looked up to cover popular formula and enter the data and retrieve the answer type sites, please vote your favorites. This data could be used to set up another section if possible.
1) http://www.ifigure.com/engineer/electric/electric.htm
2)...
Wondered if it would be of use to have a formula and calculation aid section, ie fill in the blanks and get the answeer type thing. :) Dont know how difficult it would be to do :o
Any opinions?
Hi, A simple question. I am studying to be an electrcian and finding the books sent to me dont explain the formula's very well.
For example, one of the questions is: An electric lamp has a filament resistance of 534 Ohms when connected to a 230V supply. The current flowing through it would be...
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