94 Can you name any sports which are highly affected by air resistance? SPEED AND VELOCITY IN SPORTS PERFORMANCES In sports, both speed and velocity are important measures of how athletes move, but they serve different purposes in optimising performance. Speed is more relevant in linear motion (straightline running, cycling, swimming), where the goal is to cover a distance as quickly as possible, whereas velocity is crucial in sports that involve directional changes (e.g., basketball, soccer, tennis), where how fast an athlete moves and in which direction determines the success of their performance. Speed vs velocity in performance Momentum is a vector quantity because it possesses both magnitude and direction. drill: ripetizione di un esercizio moisture-wicking: traspirante streamlined: aerodinamico stride: falcata turf: manto erboso (anche artificiale) 176 SCIENCE AND PHYSICS optimisation Speed is focused on maintaining the highest rate of motion over a distance. Athletes often train for maximum speed through sprinting drills, strength training, and improving energy efficiency to minimise wasted effort. Velocity, on the other hand, involves both speed and direction: athletes must not only be fast, but also strategic in their movements. For instance, a sprinter focuses purely on speed, while a soccer player or basketball player needs to maximise their velocity by adjusting direction quickly and maintaining control in high-speed conditions. Physics factors affecting speed Friction: less friction allows for greater speed (e.g. smooth running tracks). Air resistance : certain athletes use streamlined postures to reduce drag (e.g. cyclists and sprinters). Muscular power and acceleration: muscular power allows an athlete to exert more force in a shorter period, which is essential for rapid movement. Athletes with higher muscular power can generate more force against the ground (in activities like sprinting) or in other directions (in jumping or changing direction in sports like football or basketball). This leads to quicker acceleration. Physics factors affecting velocity Change in direction: some athletes frequently change velocity by altering direction (e.g. football or basketball). Momentum : it is a property of a moving object that is directly related to its mass and velocity. It is defined as the product of an object s mass and velocity, and it describes the quantity of motion an object has. Athletes with more mass and velocity have greater momentum which affects collisions (e.g. rugby or football). Projectile motion: it refers to the motion of an object that is launched into the air, and it is influenced by the force of gravity and air resistance. In sports, many actions involve projectile motion, such as throwing a ball, kicking a football, or shooting a basketball.