Not actually homework, but dangerousnewbie help so probably best forum to get pointers?
Wish to prevent smoke coming out of resistors Here is the situation:
I have a lamp which will requires 12 to 18 V, 2.2 watts.
I am using a pack of 10xAA batteries which produces 14.25v
Using Maths I decided I needed a 6.5ohm resistor.
Just to test I was in the correct ballpark, I tried a 10ohm resistor (because I have some) and got a reading of 1.4w OMG SMOKE
At this point I realised resistors also have a rating for the amount of current they can safely dissipate.I knew this before but sometimes it takes smoke and a binned resistor before I really learn anything.
THE QUESTIONS:
1. On a well-known electronics supplier website, some resistors have a power rating of 3/5W, which I read as three fifths, but others specifically have a rating of 0.6 - am I just reading this wrong?
2. If I connect several resistors in parallel, say I use 4 of 10ohm resistors, they will share the power load and if this reduces each resistors load to their rated level this would be safe, am I correct in this?
Wish to prevent smoke coming out of resistors Here is the situation:
I have a lamp which will requires 12 to 18 V, 2.2 watts.
I am using a pack of 10xAA batteries which produces 14.25v
Using Maths I decided I needed a 6.5ohm resistor.
Just to test I was in the correct ballpark, I tried a 10ohm resistor (because I have some) and got a reading of 1.4w OMG SMOKE
At this point I realised resistors also have a rating for the amount of current they can safely dissipate.I knew this before but sometimes it takes smoke and a binned resistor before I really learn anything.
THE QUESTIONS:
1. On a well-known electronics supplier website, some resistors have a power rating of 3/5W, which I read as three fifths, but others specifically have a rating of 0.6 - am I just reading this wrong?
2. If I connect several resistors in parallel, say I use 4 of 10ohm resistors, they will share the power load and if this reduces each resistors load to their rated level this would be safe, am I correct in this?