mwg@petrus.UUCP (Mark Garrett) (11/01/85)
++ > Assuming the rocket engine fires so smoothly as to resemble a constant force > the spaceship doesn't move in outer space, because there is no fixed object > which it could be pushing against, right? Now that we've proved that > rockets don't work (:-), how about applying Newton's law to both. > Since action = reaction, the rope exerts the same force on the monkey > as the monkey exerts on the rope (which is transmitted to the weight, > via the frictionless pulley and the massless rope). Hence both monkey and > weight rise at the same rate. Let's see that Schroedinger equation (:-)! > Dave Wallace (...!ucbvax!wallace wallace@ucbkim.berkeley.edu) Oh yeah, right. Well I TOLD you it's been a long time. Well, now that I've been sufficiently humiliated how about this one: Somebody here said they saw a film about the Lindburg flight where old CL was flying along, bored, and noticed a fly inside the plane. He started wondering if the mass of the fly contributed to the weight of the plane. If the fly is sitting on something then obviously it does. But what if the fly is flying around? What if the fly is falling? Does it make a difference if the plane is airtight or not? -Mark PS: Now let's see ... H (psi) = E (psi) ... (this might take a while....)
djw1@ukc.UUCP (D.J.Webb) (11/05/85)
In article <668@petrus.UUCP> mwg@petrus.UUCP (Mark Garrett) writes: > >Somebody here said they saw a film about the Lindburg flight where old >CL was flying along, bored, and noticed a fly inside the plane. He >started wondering if the mass of the fly contributed to the weight >of the plane. If the fly is sitting on something then obviously it does. >But what if the fly is flying around? What if the fly is falling? Does it >make a difference if the plane is airtight or not? Wether the fly is sitting on something or flying, it still contributes to the weight of the plane, since any downward force it exerts to keep itself airborn must eventually be comunicated to the plane. This reminds me of a similar problem concerning an aquaduct which is just strong enough to support the weight of water in it; if a barge sails onto the aquaduct, will it collapse? Work it out for yourselves! Cheers, Dave Webb