Strings (tennis)
In tennis, the strings are the part of a tennis racquet which make contact with the ball. The strings form a woven network inside the head (or "hoop") of the racquet. Strings have been made with a variety of materials and possess varying properties that have been measured, such as dynamic stiffness, tension retention, thickness (gauge), string texture (shape of the string), and rebound efficiency.
Double bass
An important distinction between the double bass and other members of the violin family is the construction of the pegbox and the tuning mechanism. While the violin, viola, and cello all use friction pegs for tuning adjustments (tightening and loosening the string tension to raise or lower the string's pitch), the double bass has metal machine heads and gears. One of the challenges with tuning pegs is that the friction between the wood peg and the peg hole may become insufficient to hold the peg in place, particularly if the peg hole become worn and enlarged. The key on the tuning machine of a double bass turns a metal "worm", which drives a worm gear that winds the string. Turning the key in one direction tightens the string (thus raising its pitch); turning the key the opposite direction reduces the tension on the string (thus lowering its pitch). While this development makes fine tuners on the tailpiece (important for violin, viola and cello players, as their instruments use friction pegs for major pitch adjustments) unnecessary, a very small number of bassists use them nevertheless. One rationale for using fine tuners on bass is that for instruments with the low C extension, the pulley system for the long string may not effectively transfer turns of the key into changes of string tension/pitch. At the base of the double bass is a metal rod with a spiked or rubberized end called the endpin, which rests on the floor. This endpin is generally thicker and more robust than that of a cello, because of the greater mass of the instrument.