Volume 13

The relationship between the thickness of a guitar pick and the sound quality produced by an acoustic guitar was investigated. An open E on the first string of a guitar was plucked with picks of five different thicknesses. The relative amplitudes of the first four harmonics were measured for each of the picks tested. Thicker picks produce greater amplitudes in the upper harmonics, creating a fuller sound.

Badminton smashes were recorded and analyzed at high speed, measuring the velocities of the shuttlecock and racquet head to determine the relationship between initial impact velocity and the coefficient of restitution. It was found that the coefficient of restitution follows a negative linear relationship with impact velocity. Such a relationship suggests players can most efficiently apply force at lower smash velocities.

The antioxidant properties of commercial preparations of turmeric, ginger, and thyme were compared to those of the fresh spices. The composition of the spices was determined using chromatography, which allowed for comparison of the chemical composition of the fresh and powdered spices. ABTS and DPPH tests were performed to measure the antioxidant activity of the spice extracts. The results indicate that extracts prepared from fresh turmeric and ginger exhibit greater antioxidant properties, while thyme extract had higher antioxidant capacity if prepared from powdered material.

The coefficient of restitution of a Double Yellow Dot squash ball was examined at impact velocities ranging from 13 to 29 m/s. A high-speed camera was used with video analysis to record and analyze the motion of a squash ball as it collided against a squash court wall. It was found that there is a negative linear relationship between impact velocity and COR within this velocity range.

Water clocks measure time by controlling the flow of water into a container. Ancient Persians used the sinking time of Fenjaans, bowls with holes in the center, as a metric for time. The relationship between hole diameter and sinking time of cylindrical containers was investigated. A theoretical model was derived using Torricelli’s Law and Archimedes’ Principle. The experimental relationship was found by drilling holes with diameters ranging from 2 to 13 mm in the center of nearly cylindrical stainless-steel containers and measuring their sinking time. It was found that there was a proportional relationship between the sinking time and the inverse square of the hole diameter with a proportionality constant which matched, within uncertainties, the proportionality constant predicted by the theoretical model.