Air Conditions on Pendulum Movement
Kaden Leung
Stratford Hall
Floor Location : J 130 E

In 1968, Bob Beamon made the world record for long jump of 8.9 meters. Many people theorized that his world record was only obtained due to the air temperature and humidity. In 2012, Takuo Toda attempted to beat his world record of longest paper airplane flight duration of 29.2 seconds. He said that he was not able to beat his record due to the high humidity of the environment. In baseball, as the baseball flies through the air, its flight path is dependent on the air conditions of its environment. The University of Massachusetts made an experiment on how baseball temperature affects how far a baseball travels. In this experiment, I have observed how air temperature and humidity changes the time a pendulum stays in motion. In this experiment, two independent variables were tested; one changing the air temperature and the other changing the air relative humidity.

My hypothesis for the air temperature experiment was ‘if the temperature of the air inside the container increases, the time a pendulum stays in motion will increase’. As the temperature of an environment is increased, the intermolecular forces between the air molecules (mainly nitrogen and oxygen) decreases. A decrease of intermolecular forces decreases the density of the air. With a decreased density, the pendulum will come into contact with less air molecules and transfer less kinetic over time. With less air drag, the pendulum will therefore stay in motion for a longer time. My hypothesis for the air humidity experiment was ‘if the humidity of the air inside the container increases, the time a pendulum stays in motion will increase’. As the amount of water vapour increases inside an environment, the amount of nitrogen and oxygen molecules decrease because they are displaced by water molecules. The gas state of water has less mass than the gas state of nitrogen and oxygen so therefore humid air is less dense than dry air. With a decreased density, the pendulum will stay in motion for a longer time.

In this experiment, pendulums were put into containers. The air conditions of the experiments were changed by using ice (lowers temperature), a hot lamp (increases temperature), a hair dryer (lowers humidity) and a steam iron (increases humidity). These air conditions were measured using a thermometer and a hygrometer.

The results found in the experiment matched my hypotheses. As the temperature increased, the time a pendulum stayed in motion increased. As the temperature increased, the time a pendulum stayed in motion increased.

With the information retrieved from this experiment, many world records can be changed. For example, if the temperature and humidity of the air is just right, a person may be able to achieve a world record for a certain Summer Olympic Sport. Locations of the Olympics can have a great effect on the performance of an athlete. Due to the fact that the air conditions are not controlled in different Olympic years, we can take them to our advantages to possibly beat world records.