help pls

[NWDS]

Afternoon all thanks for your time, Iam stuck on this I cannt get me head around it, when Iam given resistance and power I struggle to work out voltage or current.

Example 1, if a 0.5 watt lamp consumes a current of 200mA. What voltage of battery should be fitted ????.

Example 2, What current does a 3000 watt electric fire draw from the supply if its resistance is measured at 19.2 ohms

NDWS

 

[Andy™]

1: V= p/i

2: I = √ p/r

EDIT: why does the above formula change to lower case?

 

[a1spark]

Thi is better !

P

I V

P

2

I R

V

I R

a1spark

 

[Andy™]

Thi is better !P P V

or 2 and

I V I R I R

a1spark

for those who think all thats in foreign, click 'quote' (on the other post!) and see what it then says!

 

[a1spark]

for those who think all thats in foreign, click 'quote' (on the other post!) and see what it then says!

Andy if you were not so quick to jump in with unhelpful remarks then you would have seen I was struggling with the type it appeared to close up on itself after being posted.....I dont know why that was ..it was ok when I pressed the submit button......The triangle metrhod I posted is a better method ,

 

[Andy™]

Andy if you were not so quick to jump in with unhelpful remarks then you would have seen I was struggling with the type it appeared to close up on itself after being posted.....I dont know why that was ..it was ok when I pressed the submit button......The triangle metrhod I posted is a better method ,

trying to post like you did in your original quote never works once posted, but if you click 'quote' on your post, it shows up exactly how it should. so stop your moaning.

 

[NWDS]

Example 1

V= P/R 0.5/200 = 0.0025, because its mA I need to move the decimal point 3 places to the right ????, this will give me 2.5v ???

NWDS

 

[a1spark]

Andy

wouldnt your life be happier if you just gave the relevant advice without having to add casual remarks ?

 

[Andy™]

Andy wouldnt your life be happier if you just gave the relevant advice without having to add casual remarks ?

i gave advice - to make your post show correctly, click quote'.

whats the problem?

 

[Andy™]

Example 1V= P/R 0.5/200 = 0.0025, because its mA I need to move the decimal point 3 places to the right ????, this will give me 2.5v ???

NWDS

or just make it

V= P/R 0.5/0.2=

2.5V is correct

 

[a1spark]

i gave advice - to make your post show correctly, click quote'.whats the problem?

I appreciated your thanks....but did you have to finish off with " So Stop your Moaning "...are you sure you are not in breach of forum rules with the tone of your replies ?

 

[Andy™]

I appreciated your thanks....but did you have to finish off with " So Stop your Moaning "...are you sure you are not in breach of forum rules with the tone of your replies ?

and there was nothing wrong with any of your posts ranting on about how your NIC accessor is God and you wont listen to anyone else?

 

[NWDS]

Example 2

P/R = V ( as Example 1 )

3000/19.2 = 156.25

V/R = I

156.25/19.2 = 8.13

This is not the answer I was given ( not the same book either Andy ), am I right or not because the self doubt is doing my napper IN.

NWDS

 

[Andy™]

Example 2P/R = V ( as Example 1 )

3000/19.2 = 156.25

V/R = I

156.25/19.2 = 8.13

This is not the answer I was given ( not the same book either Andy ), am I right or not because the self doubt is doing my napper IN.

NWDS

note the square root in my formula! (i had missed 'I=', so may have looked different)

 

[NWDS]

Sorry Andy, cannt headbangheadbang think were am I going wrong :coat :coat:coat:coat

NWDS

 

[NWDS]

STILL headbangheadbang

 

[Andy™]

2: I = √ p/r

I= √ (3000 /19.2) = 12.5A

 

[a1spark]

and there was nothing wrong with any of your posts ranting on about how your NIC accessor is God and you wont listen to anyone else?

So thats whats eating you !..Your still harping back to that post ?????

I did not rant on I answered other posters replies with sensible honest opinion

..yourself and others did not agree with my point ,which I accept and I finally ended participation in the thread cos it wasnt getting anywhere ! or benefitting the forum.

What was wrong with that ?...

I certainly didnt post in the manner you have been posting in reply to my posts....I wouldnt lower my self to that level !...try and be a bit more generous with your remarks to people even if you dont agree with their point of view...you will be a happier fella for it..!....Heres Hoping !

a1spark

 

[NWDS]

Do not want to get involved with bickering fellas, I would just like to say a big thank you to both of you, without your input the forum would suffer and that would be a shame.

NWDS

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