Day 4: Definitive battery vs peanut

We’re wrapping up our discussion of the battery vs peanut, and though students are just about willing to accept that a peanut has almost twice as much energy as a battery, a large fraction of the class still thinks that the battery’s gradual release of energy over a long time might possibly allow its energy content to be greater.

So we did one more experiment to test this. We simultaneously measured the temperature increase of 80mL of water when heated by a burning peanut and a shorted battery.

IMG 1058

Here’s the data

Screen Shot 2013 09 07 at 12 12 58 AM

Of course, there are some other interesting observations that come up. Here’s what the battery looks like after 3 hours of immersion in water. Note that a battery not in a circuit looks almost identical to a new battery after being immersed in water.

IMG 1063

Similarly, the terminals of the battery holder experience what looks like a chemical reaction as well.
IMG 1064

Advertisements

About John Burk

The ramblings of a physics teacher.
This entry was posted in Uncategorized and tagged , . Bookmark the permalink.

2 Responses to Day 4: Definitive battery vs peanut

  1. Mr. Kilbane says:

    Cool experiment. How’d you short the battery for the exp?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s