nanobiscotte resistor question

[Captain]

So with the 18650 and the White Rebel star I figured I need a 1ohm 4 W resistor so I figure a 1ohm 5W resistor should Do am I right?

[Forgetful Jedi Knight]

So with the 18650 and the White Rebel star I figured I need a 1ohm 4 W resistor so I figure a 1ohm 5W resistor should Do am I right?

Right now, I am going to say no, that doesn't sound right. What values are you using for your calculations?

[Captain]

Umm I followed the formula in the users manual for the Nano Biscotte. (3.7v - 3.1v) / 1A then for Watts well 3.7v x 1a. Thats what I guessed.

[Forgetful Jedi Knight]

Umm I followed the formula in the users manual for the Nano Biscotte. (3.7v - 3.1v) / 1A then for Watts well 3.7v x 1a. Thats what I guessed.

Ummm - computer says... Nah. It's more like 1 Ohm, 1 Watt resistor. Your calculation for the wattage was WAY off.

[Captain]

Can you show me how you figured it out so I can see what i did wrong in my calculations?

[Captain]

Also i don't see any 1ohm 1w resistors on the store site. Would a 2w suffice?

[Forgetful Jedi Knight]

Can you show me how you figured it out so I can see what i did wrong in my calculations?

From the top...

R = (3.7 - 3.1) / 1 = .6 ohm rounds up to -> 1 Ohm

P = R * I^2 = .6 * 1^2 = .6 Watt rounds up to -> 1 Watt

Even if you substituted the 1 ohm for .6 ohm in the second calculation, you would still get to 1 Watt

Got it now?

[Captain]

So I was right about it and my father not so right. I hope radio shack sells 1o 1w resistors.

[Forgetful Jedi Knight]

Also i don't see any 1ohm 1w resistors on the store site. Would a 2w suffice?

You could try Radio Shack if there is one nearby you. Otherwise a 1 Ohm 2 Watt would work if you couldn't get the other one.

[Captain]

Thank you for all your help. Now I can complete my order finally.