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Physics of Pole Vaulting ﻿ ﻿Pole vaulting illustrates how one type of energy is converted into another type of energy. During pole vaulting, all of the jumper's kinteic energy (the energy of motion) is converted into the gravitational potential energy (the energy associated with working against gravity) of the jump height. ﻿__Conversion of Energy__ When a pole vaulter sprints toward the bar, he or she is building up kinetic energy. When the vaulter transfers his or her movement to the pole, he or she is transferring the kinetic energy built up in the sprint into potential energy stored into the pole and the vaulter's muscles, which pushes the vaulter into the air and over the bar. ﻿__Gravity__ In order to lift the pole vaulter into the air, the gravitational potential energy in the pole mus t be at least enough to overcome the downward pull of gravity, which on Earth pulls at 9.8 meters oer second sqaured. If the pole does not have enough energy to beat gravity, additional energy stored in the vaulter's muscles will make up for the lack of energy. ﻿__Conservation of Energy__ An important principle in physics in the Conservation of Energy. This principle is displayed in pole vaulting and states that energy can never be created or destroyed; however, it can be transferred from one type to another. The transfer of kinetic energy to gravitational potential energy is what enables pole vaulters to leap so high. In a perfect world a vaulter wants all of his kinetic energy to transfer into gravitational potential energy but realistically this impossible since some energy will be lost to heat, friction, or wobbling in the pole. The better a vaulter's technique is, the more energy he or she will be able to transfer and the higher he or she will vault. ﻿The equation for kinetic energy is expressed as 1/2mv 2 ﻿ where m equals the mass of the vaulter and v equals the velocity of the vaulter's approach. Gravitational potential energy is expressed as mgh where m equals the mass of the vaulter, g is the acceleration due to gravity on Earth, and h equals the height of the jump. Because gravity plays a major role in pole vaulting, we see that if pole vaulting occured where there was less gravity (such as on the moon) then the height of a vault would increase proportionately.

﻿ ﻿By assuming that 100% of kinetic energy is converted into gravitational potential energy, the equations can be set equal to each other. The mass appears on both sides; therefore, it cancels out and the resulting equation is 1/2 v^2=gh. To calculate the theoretical height of a pole vaulter the equation can be solved for h resulting in h=1/2 (v^2/g).

This expression needs to be adjusted slightly to account for the fact that the vaulter has a height above the ground. This height is different from the height "h" we are trying to figure out. It is based on--but not exactly the same as-- how tall the vaulter is. Rather, it is based on something called "center of mass." The "center of mass" is defined as the point in a body which acts as if all the body's mass were concentrated there. For a person, the center of mass is roughly half of how tall he or she is. This varies, though, by body type.

﻿Here some videos to help put it all together: <span style="background-color: #ffffff; color: #000000; font-family: 'Arial Black',Gadget,sans-serif;"> <span style="background-color: #ffffff; color: #000000; font-family: 'Arial Black',Gadget,sans-serif;">media type="youtube" key="bgMCm3AAPJU" height="390" width="480" <span style="background-color: #000000; color: #ffffff; font-family: 'Arial Black',Gadget,sans-serif; line-height: 0px; overflow: hidden;">

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<span style="background-color: #000000; color: #ffffff; font-family: 'Arial Black',Gadget,sans-serif; line-height: 0px; overflow: hidden;">These are just for fun:

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