Article View: sci.electronics
Article #21585Re: HV Cap Fun!
From: Arnie Frisch
Date: Thu, 01 Jun 1989 15:40
Date: Thu, 01 Jun 1989 15:40
18 lines
1516 bytes
1516 bytes
In article <20772@quacky.mips.COM>, vaso@mips.COM (Vaso Bovan) writes: > A Paradox of Capacitor Energy Storage > Consider an ideal 2uF (for computational ease) capacitor charged by a 10 volt > source. Eventually, the energy stored is (1/2)*CV^2=100 joules. > > Consider the capacitor to be isolated from the voltage source, and then > directly shorted across an identical (ideal) capacitor. Eventually, the > voltage across each capacitor will be 5V. Now, there are two equally > charged capacitors, each storing (1/2)*CV^2= 25 joules, for a total of > of 50 joules. What happened to the other 50 joules ? In real circuits, infinite currents are not allowed - either the inductance or resistance of the circuit prevents the current from reaching infinite value. In this circuit, no resistance is specified and no inductance is specified, so I guess the current - on paper - could be infinite for zero time (i.e. an impulse). Just like I guess the energy - on paper - gets radiated into free space.
Technical Details
Message-ID:
<5255@tekgvs.LABS.TEK.COM>Path:
arc1-ca.pugleaf.net!utzoo!attcan!uunet!zephyr!tektronix!tekcrl!tekgvs!arniefReferences:
<4924@m2c.M2C.ORG> <3806@mit-amt> <20772@quacky.mips.COM>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!zephyr!tektronix!tekcrl!tekgvs!arnief From: arnief@tekgvs.LABS.TEK.COM (Arnie Frisch) Newsgroups: sci.electronics,sci.physics Subject: Re: HV Cap Fun! Summary: I must have heard this first about 30 years ago...... Message-ID: <5255@tekgvs.LABS.TEK.COM> Date: 1 Jun 89 15:40:07 GMT References: <4924@m2c.M2C.ORG> <3806@mit-amt> <20772@quacky.mips.COM> Followup-To: sci.electronics,sci.physics,poster Organization: Tektronix Inc., Beaverton, Or. Lines: 18