Cobweb

Cobwebs are intangible in the sense that the Player can walk through them. But cobwebs do have an "effect hitbox" that affects the Player if they come into contact with it.

If the overlap is more than 0.001m wide, the Player's movement will be slowed down.

If the overlap covers less than 0.001m, the Player is able to move normally while "touching" the cobweb's borders. For this reason, it is possible to walk along a block's edge with a cobweb on top of it.

Vertical Movement:
Vertical speed is slowed down by a factor of 20, and is reset on every tick.

Jumping is severely limited, and reaches just 0.021m in height.

Furthermore, the Player will immediately start falling at a constant rate of -0.00392 m/s.

Horizontal Movement:
Horizontal speed is slowed down by a factor of 4, and is reset on every tick.

This means the Player will move at a constant speed of 0.03185 b/t when sprinting on ground, or 0.00637 b/t while airborne.

Or, respectively with 45° Strafe, 0.0325 b/t when sprinting on ground, and 0.0065 b/t while airborne.

Calculations: