Mass in special relativity the mass of a moving particle." When the relative velocity is zero, formula_33 is simply equal to 1, and the relativistic mass is reduced to the rest mass as one can see in the next two equations below. As the velocity increases toward the speed of light "c", the denominator of the right side approaches zero, and consequently formula_33 approaches infinity. In the formula for momentum the mass that occurs is the relativistic mass. In other words, the relativistic mass is the proportionality constant between the velocity and the momentum. While Newton's second law remains valid in the form the
Biomechanics of sprint running ground forces is also very important. Weyand et al. (2000) came up with the following equation for determining sprint velocity: where formula_2 is the sprint velocity (m/s), formula_3the step frequency (1/s), formula_4 the average force applied to the ground (N), formula_5 the body weight (N), and formula_6 the contact length (m). In short, sprint velocity is reliant on three main factors: step frequency (how many steps you can take per second), average vertical force applied to the ground, and contact length (distance your center of mass translates over the course of one contact period). The formula was tested by having