Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tektronix!hplabs!sri-unix!spears@nrl-aic From: spears%nrl-aic@sri-unix.ARPA Newsgroups: net.physics Subject: Advertisement claims Message-ID: <265@sri-arpa.ARPA> Date: Tue, 11-Jun-85 08:01:53 EDT Article-I.D.: sri-arpa.265 Posted: Tue Jun 11 08:01:53 1985 Date-Received: Sat, 15-Jun-85 06:01:27 EDT Lines: 28 From: William Spears I have just recently come across an interesting advertisement for a radio that runs on muscle power alone - just turn the crank 10 times and the radio (and encased flashlight!) will run for an hour and a half. Judging by the measurements given for the radio, and by looking at the picture, the crank seems to be about 4 inches long. I assume a healthy person will generate 40 lbs of force over the circumference traced by the crank handle (This seems like an absurdly high force). After 1 turn the person has done slightly more than 80 ft. lbs. of work (or roughly 110 Joules). In 10 turns roughly 1100 Joules of work has been done. Assuming a 1 Watt (1 J/s) radio (and flashlight) the device can operate for perhaps 1000 seconds (assuming high efficiency). This is roughly 17 minutes. My question: How does his radio function for 1.5 hours? Can I assume a .1 Watt radio? Also I have assumed that the person wants to build up his/her biceps with 40 lbs of force - but this assumption helps the claim of the advertisement. Does anyone have one of these radios? Bill Spears NRL-AIC