Burning Pencil Informal Lab Report by Matthew K Chak
Purpose: See if a 12V 1A power source can successfully burn a pencil.
Hypothesis: If we were to connect the ends of a pencil to a 12V 1A power source, then it will burn the pencil.
Theoretical Background: Graphite, the material used in pencils, is a form of crystalline carbon found in metamorphic and igneous rocks. It is also extremely heat resistant. Graphite forms under extreme heat and pressure. In order to form graphite, 75000 PSI and temperatures of 750 C (1382 F) must be exerted. When we connect the power supply to the pencil, the energy moves through the pencil. This causes the molecules to move around and produce heat. We can then calculate the amount of heat exerted using the formula Q=mc(delta)T, where Q is heat in joules, m is mass, c is specific heat, and t is temperature ((delta) T is change in temperature). The energy we released should have been enough to burn the pencil.
Materials and Equipment:
The pencil greatly increased its temperature within the first minute or so of the experiment. As the experiment went along, the pencil slowly started to drop in temperature due to the energy source losing power. While the pencil didn’t catch on fire, it did smoke and burn the paper.
Our hypothesis was incorrect – there wasn’t enough energy to burn the pencil. Our purpose was fulfilled - we did learn that a 12V 1A power source couldn’t burn the pencil. If you would want to continue the investigation, use a different power source that is stronger.