Subject :- Applied Physics 2.

Topic :- Laser.

Difficulty :- Low.

: The curl of a vector field at any point signifies how much the vector quantity curls or twists around that point. For example, we may consider water going down the drain. In this motion water swirls in rotation. The rotation has a direction and is about the direction of motion. The curl of a vector field is a vector field and is written as∇ ⃗ X B ⃗