# How to calculate change of velocity after hitting water?

• Number1koer

#### Number1koer

Me and a Partner are presenting the physics of diving as our final in physics. He wants a ton of detail about the activity we choose so I thought it would be a good idea to show the difference from a cannonball vs a normal dive and the change in velocity that occurs with both, and also how much of your energy is transferred into the water. My partner is going to be filmed jumping off of a diving board, and I will then take the video and put it into logger pro. I am wondering if there is a fairly simple way to get the info I need. I am also wondering what info I will need, like if I will need her mass to calculate the change in velocity. If there isn't really a way to get exact numbers out of this, it would also be helpful for a simple explanation of what effects impact on water. (Mass, How velocity impacts it, etc.)

## Answers and Replies

it would also be helpful for a simple explanation of what effects impact on water. (Mass, How velocity impacts it, etc.)
What do YOU think effects the impact and the resultant speed in the water? You HAVE to show at least some effort if you want help on this forum.

Have you done video analysis of the motion of anything else? The basic idea is that you need to know how far she moves between video frames, and the time that elapses between video frames. The ratio is the average velocity. I just did a google search for video analysis of diver and got lots of hits with lots of details.

how much of your energy is transferred into the water
Why would the answer differ from "all of it"?

Why would the answer differ from "all of it"?
Wouldn’t you still have kinetic energy because you are still moving?

Wouldn’t you still have kinetic energy because you are still moving?
I usually stop before hitting the bottom of the pool.