Throughout the KMT unit, we have been presented with experiments that involve the following variables: temperature, volume, pressure, and number of particles. The Can Crusher is not different in this aspect. Temperature in our experiment is seen both in the water temperature, and in the amount of time the can is left on the fire. Volume is seen in both the can volume and in the measurement of percent crush. The number of particles is seen in the initial water amount added to the can to start the experiment, and finally, pressure is obviously a factor (though not measured directly) throughout the experiment.

What is different in the Can Crusher experiment is that none of the variables (temperature, volume, pressure, or number of particles) are actually held constant throughout the experiment. In this case, identifying a simple relationship between two variables is impossible. In other words, the can crushing cannot be explained by simply stating that as pressure increases, volume decreases. The temperature was not held constant and neither were the number of particles in the can (the can remains open to the air as it is being heated, so particles in the can are allowed to escape). Stating that as temperature decreases, volume decreases cannot explain the entire phenomenon either as pressure is also changing through the experiment.

Explaining the can crush will require that you focus on what particles are doing on a microscopic level throughout the entire process. The can crush simulation includes a check box labeled "see-inside"; the simulation is included again below so you can perform a trial (or trials) while this box is checked. Be sure to observe the particles in the can throughout the entire can crush, then answer the questions below.