The faster an object moves, the more massive it becomes. This mass increase is given by . An important consequence of mass increase is a violation of the principle of conservation of mass . Mass can be converted into energy and vice versa. In addition to the violation of mass conservation above, it can be shown that conservation of energy is violated, i.e. the energy you put into accelerating an object doesn't all show up as the object's energy.
Nothing can travel faster than light.
If you are accelerating an object towards the speed of light, its mass increases without bound, making it harder and harder to increase its speed. As a consequence, a massive object must always travel at less than the speed of light. Newton's Laws of Motion are approximations to Special Relativity that are applicable only at low speeds. In other words, Special Relativity is a generalization of Newton's Laws of Motion. Nevertheless, with sensitive experimental equipment such as atomic clocks, the predictions of Special Relativity have been verified to high precision.