î

î, pronounced as "eye-cap", symbol used in Physics and Mathematics to denote a unit vector in the forward X-axis direction. This is the direction away from the Origin and parallel to the X-axis, in the chosen frame of reference.

ELI5:
When you draw physics shit, you make the graph lines, see, like the X-axis and the Y-axis. And if it's 3D, then there's also a Z-axis. They're like, ya know, the East-West line, the North-South line, and the Up-Down line. And the î is the name of the "East" direction in this graph. The horizontal rightwards.

The particle was only accelerated in the î direction, hence only the x-component of its velocity will only be affected.

î

î, pronounced as "eye-cap", symbol used in Physics and Mathematics to denote a unit vector in the forward X-axis direction. This is the direction away from the Origin and parallel to the X-axis, in the chosen frame of reference.

ELI5:
When you draw physics shit, you make the graph lines, see, like the X-axis and the Y-axis. And if it's 3D, then there's also a Z-axis. They're like, ya know, the East-West line, the North-South line, and the Up-Down line. And the î is the name of the "East" direction in this graph. The horizontal rightwards.

The particle was only accelerated in the î direction, hence only the x-component of its velocity will only be affected.