This is a multi-part message in MIME format. ------=_NextPart_000_0015_01C6B78F.5DFF8130 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Ken, Power(Watts) are the RATE of using energy(Joules/Second), 100 watt bulb is using energy at 100 Joules per Sec, or J/S. The total energy used is the the product of Watt * Seconds, which is Joules again. Mike Hagen Hagen Engineering Crestline, Ca. Mike@HagenEng.com (909) 338-5521 ------=_NextPart_000_0015_01C6B78F.5DFF8130 Content-Type: message/rfc822 Content-Transfer-Encoding: 7bit Content-Disposition: attachment Reply-To: "Microcontroller discussion list - Public." From: "Ken Walker" Sender: To: "'Microcontroller discussion list - Public.'" Subject: RE: [EE] : Interpreting power with time Date: Fri, 4 Aug 2006 05:47:26 -0700 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0010_01C6B78F.5DFD1030" X-Mailer: Internet Mail Service (5.5.2657.72) X-Spam-Score: 0.13 X-Spam-Flag: NO X-Scanned-By: MIMEDefang 2.42 X-Topics: [EE] X-BeenThere: piclist@mit.edu X-Mailman-Version: 2.1.6 List-Unsubscribe: , List-Help: List-Subscribe: , X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-UoM: Scanned by the University Mail System. Seehttp://www.itservices.manchester.ac.uk/email/filtering/information/for details. This is a multi-part message in MIME format. ------=_NextPart_000_0010_01C6B78F.5DFD1030 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit It's always confused me sometimes. My example of confusion. A 100 watt bulb, now i know watt is watts/second, so does a 100w bulb use 100w/second or 6000 w/min or 360,000 w/s. Well if it did it'd be well beyond my income to pay for a single bulb yearly. so it must be 100w/hour, so does that mean the bulb is actually using 100/360000 4.7E-4w/second ! And if you put 12volts across a 1ohm resistor, the power put in would be 12 watts, now is that also w/second or w/hour ! Over here ( UK) a kw is approx 5 pence ( if you know the actual price per kw please let me know ;) so does a l00w light bulb cost 5p/10hours. just a little bit more confusion for some :o) Ken > -----Original Message----- > From: piclist-bounces@mit.edu > [mailto:piclist-bounces@mit.edu]On Behalf > Of Gerhard Fiedler > Sent: 04 August 2006 1:14pm > To: piclist@mit.edu > Subject: Re: [EE] : Interpreting power with time > > > Mohamed Ismail Bari wrote: > > > I want to know how this power can be > > releated to time. Should I say the dissipation as 1W/Sec or > 1W/min or > > 1W/Hr?????.... (My guess is 1W/Sec) I am sure this is a 7th > grade math. > > Probably, I was not paying attention when I was in 7th grade..;-). > > That's not math, that's physics, more specifically about the > relationship > the different units have with each other. Which is a quite > nice and logic > system -- if you use SI units, and not one of the different customary > systems. > > A quick overview: http://physics.nist.gov/cuu/Units/units.html (you find the Watt and the Joule there, too). Gerhard -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist ------=_NextPart_000_0010_01C6B78F.5DFD1030-- ------=_NextPart_000_0015_01C6B78F.5DFF8130 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist ------=_NextPart_000_0015_01C6B78F.5DFF8130--