[zdyn5]

Not if they eject the trash above escape velocity

[smallmancontrov]

Charge up the electromagnetic trash cannon!

[greggsy]

You’d presumably need some kind of trash compactor to maximise the efficiency.

[KineticLensman]

This presumably was Humanity’s fall back if the fusion drives didn’t stop the Kzinti

[brookst]

Aka the trash to kinetic weapon converter.