Are you considering the pole as part of that mass? If so, don't. We are assuming the pole's mass is negligible, and if we were to allow for its mass that will make it harder since some of the pole's mechanical energy will have gone into raising the pole to the vertical.Derek1997 said:center of mass
To maximize vault height, vaulters bend their body around the bar (as shown in the figure below). In doing so, their center of mass (the red dot) can actually pass underneath the bar, while enabling their body to pass over the bar (the black dot). This means that the bar can actually be placed higher than the maximum height reached by the center of mass of the vaulter.pole vaulters do not use their strength to lift themselves over the bar. Instead, they primarily use the pole as an intermediate tool to help them convert their kinetic energy into gravitational potential energy (height). Good sprint speed combined with good gymnastic ability are what is needed to effectively utilize the pole.Air resistance also plays a role in how high a vaulter can vault. In areas of higher altitude, the air is less dense which reduces air resistance when running. This in turn means that the vaulter can reach a higher speed before the vault, which results in a higher vault. To give you an idea, if a vaulter running at 10 m/s at sea level can run 2% faster at high altitude, then he can vault about 21 cm higher at high altitude. enough?haruspex said:Are you considering the pole as part of that mass? If so, don't. We are assuming the pole's mass is negligible, and if we were to allow for its mass that will make it harder since some of the pole's mechanical energy will have gone into raising the pole to the vertical.
You are right that the athlete's mass centre may be external, but can you explain how, exactly?
That (passing the mass centre below the bar) is certainly part of it, but I doubt it would get another 0.4m. You are still missing an important component hinted at in several posts.Derek1997 said:I hope that can explain part B?
Horizontal velocity to vertical velocity change?haruspex said:That (passing the mass centre below the bar) is certainly part of it, but I doubt it would get another 0.4m. You are still missing an important component hinted at in several posts.
Look at the position of the vaulter's body in relation to the part of the pole the vaulter is holding. How does this change in going from ground level to going over the bar?
No, not velocity; position.Derek1997 said:Horizontal velocity to vertical velocity change?