Does weight affect how far you jump?
For the same leg strength / jumping method, weight affects how far one can jump.
Acceleration = Force / Mass
With more mass, you cannot accelerate yourself as much when you jump with the similar force. Imagine trying to jump with a small backpack full of sand strapped to your back. Your strength hasn't altered. That is, the amount of force you can deliver hasn't altered, but your mass has. You can't jump as high.