Science Buddies: "Ask an Expert"

my project is on crater impact due to mass and velocity where my independent variable is mass and velocity.

How can I measure or track velocity.

I would recommend to only have one independent variable so that the other variables could be constants, which are controls. Aside from that, if you want to calculate average velocity, you would record the distance and divide by the time. So if an object travels 20 inches in 5 seconds, then the speed would be 20 divided by 5, or four inches per second.

Thanks,

Also can u suggest some catchy topic for this project