Conservation of Powers

This is a world where everyone awakens their special powers at the age of 16. But the essence of superpowers is the local manipulation of physical laws - someone can change the coefficient of friction, someone can control the intensity of the electric field, and someone can adjust the refractive index of light. Key Rule: All powers are subject to basic laws such as conservation of energy and conservation of momentum. As much work as you do with your powers, you have to absorb the same amount of energy from the environment.