Emitter Emission tab: Motion Inheritance quicktab
If the emitter or the emission object moves or rotates, particles can inherit their speed and direction from them. These settings will have no effect if the emitter or emission object are completely static.
Please note : if using expressions to animate the emitter or emission object then please see the Priorities section. It is important that the animation is done before the emission of particles to correctly inherit the velocity.
Use Motion Inheritance
Check this switch to enable motion inheritance.
If checked, this switch will cause the particles to inherit speed and direction from any linear motion of the emitter.
If checked, this switch will cause the particles to inherit speed and direction from any rotational motion of the emitter.
A value of 100% in this field will add the full contribution of the emitter's motion to that of the particles. If set to 0%, it would be the same as if motion inheritance was not used.