On Tue, 11 Feb 2020 10:09:18 -0800, Bob Kuykendall wrote:

On Tuesday, February 11, 2020 at 5:15:04 AM UTC-8, Tim Newport-Peace
wrote:

Not Quite True.
Since a charged battery contains a greater total amount of energy than
a dead battery, the earth's gravity will pull more strongly on it.
But you will have trouble measuring the difference ;¬))

But seriously, no. Energy in and of itself has no mass. A an old-time
watch or windup toy has the same mass regardless of whether it is wound
or unwound.

....but an electron does have mass, just not very much:
9.1093837015 × 10^-31 kg

Not that it matters, because as many electrons flow into a discharging
battery as flow out.


--
Martin | martin at
Gregorie | gregorie dot org