Jumping - Wikipedia. Jumping or leaping is a form of locomotion or movement in which an organism or non- living (e. Jumping can be distinguished from running, galloping, and other gaits where the entire body is temporarily airborne by the relatively long duration of the aerial phase and high angle of initial launch. Some animals, such as the kangaroo, employ jumping (commonly called hopping in this instance) as their primary form of locomotion, while others, such as frogs, use it only as a means to escape predators. Jumping is also a key feature of various activities and sports, including the long jump, high jump, and show jumping. Physics. Any solid or liquid capable of producing an opposing force can serve as a substrate, including ground or water. Examples of the latter include dolphins performing traveling jumps, and Indian skitter frogs executing standing jumps from water. Jumping organisms are rarely subject to significant aerodynamic forces and, as a result, their jumps are governed by the basic physical laws of ballistic trajectories. Consequently, while a bird may jump into the air to initiate flight, no movement it performs once airborne is considered jumping, as the initial jump conditions no longer dictate its flight path. Following the moment of launch (i.
The launch angle and initial launch velocity determine the travel distance, duration, and height of the jump. The maximum possible horizontal travel distance occurs at a launch angle of 4. Muscles (or other actuators in non- living systems) do physical work, adding kinetic energy to the jumper's body over the course of a jump's propulsive phase. This results in a kinetic energy at launch that is proportional to the square of the jumper's velocity. The more work the muscles do, the greater the launch velocity and thus the greater the acceleration and the shorter the time interval of the jump's propulsive phase. Jump Jump, Jump from one liana to another and try not to fall! Jump Lyrics: Jump Jump / You should know, you should know that ahhh / Kris Kross is not having anything today / As we stand there totally krossed out / We commence to make you (Jump Jump) / The. Jump song for children. Jumping, dancing, sing along song for kids. Jump, jump, jump, jump. As a result, many jumping animals have long legs and muscles that are optimized for maximal power according to the force- velocity relationship of muscles. The maximum power output of muscles is limited, however. To circumvent this limitation, many jumping species slowly pre- stretch elastic elements, such as tendons or apodemes, to store work as strain energy. Such elastic elements can release energy at a much higher rate (higher power) than equivalent muscle mass, thus increasing launch energy to levels beyond what muscle alone is capable of. A jumper may be either stationary or moving when initiating a jump. In a jump from stationary (i. In a moving jump or running jump, the jumper introduces additional vertical velocity at launch while conserving as much horizontal momentum as possible. Unlike stationary jumps, in which the jumper's kinetic energy at launch is solely due to the jump movement, moving jumps have a higher energy that results from the inclusion of the horizontal velocity preceding the jump. Consequently, jumpers are able to jump greater distances when starting from a run. Anatomy. Red marks indicate bones substantially elongated in frogs, and joints that have become mobile. Blue indicates joints and bones that have not been modified, or are only somewhat elongated. Animals use a wide variety of anatomical adaptations for jumping. These adaptations are exclusively concerned with the launch, as any post- launch method of extending range or controlling the jump must use aerodynamic forces, and thus is considered gliding or parachuting. Aquatic species rarely display any particular specializations for jumping. Those that are good jumpers usually are primarily adapted for speed, and execute moving jumps by simply swimming to the surface at a high velocity. A few primarily aquatic species that can jump while on land, such as mud skippers, do so via a flick of the tail. Limb morphology. Typical characteristics of jumping species include long legs, large leg muscles, and additional limb elements. Long legs increase the time and distance over which a jumping animal can push against the substrate, thus allowing more power and faster, farther jumps. Large leg muscles can generate greater force, resulting in improved jumping performance. In addition to elongated leg elements, many jumping animals have modified foot and ankle bones that are elongated and possess additional joints, effectively adding more segments to the limb and even more length. Frogs are an excellent example of all three trends: frog legs can be nearly twice the body length, leg muscles may account for up to twenty percent of body weight, and they have not only lengthened the foot, shin and thigh, but extended the ankle bones into another limb joint and similarly extended the hip bones and gained mobility at the sacrum for a second 'extra joint'. As a result, frogs are the undisputed champion jumpers of vertebrates, leaping over fifty body lengths, a distance of more than eight feet. As noted above, power output is a principal determinant of jump distance, but physiological constraints limit muscle power to approximately 3. Watts per kilogram of muscle. When the catch is released, the apodeme rapidly releases its energy. Because the apodeme releases energy more quickly than muscle, its power output exceeds that of the muscle that produced the energy. This is analogous to a human throwing an arrow by hand versus using a bow; the use of elastic storage (the bow) allows the muscles to operate closer to isometric on the force- velocity curve. This enables the muscles to do work over a longer time and thus produce more energy than they otherwise could, while the elastic element releases that work faster than the muscles can. The use of elastic energy storage has been found in jumping mammals as well as in frogs, with commensurate increases in power ranging from two to seven times that of equivalent muscle mass. One category of such exercises. Anuran Locomotion: Structure and Function. Jumping performance of semiacquatic, terrestrial, and arboreal frogs. Smithsonian Contributions to Zoology 2. Jumping ability of anuran amphibians. Advances in Veterinary Science and Comparative Medicine 3. Work and power output in the hindlimb muscles of cuban tree frogs Osteopilus septentrionalis during jumping.
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