Are your powers possible?

So here's something I came up with while trying to think of ways to enhance JaK's powers. What are the scientific limitations of his abilities, heck if his powers were even plausible what could they grow to, and can I scientifically link them together.

EX: speedsters can share speed, but only with things in motion already because newtons law says you can not speed up anything not in motion already.

Also phasing through objects leaves your kinetic energy inside said object causing it to double up and explode if you're a speedster.

So basically I'm asking what are the side effects and pausible, extents, and limitations of your OC characters powers if you were to explore them?