Recent content by ruairilamb

Thanks for all the replies. I think for now this problem is slightly beyond my ability. I will tackle some simpler problems first.

The minus sign is due to the photons being ejected downwards. Thanks for the reply.

Before the engine is switched off: $$P_{Initial rocket} = (m_{i}c, 0)$$ $$P_{photons} = (E/c, -p_{photons})$$ where E is the energy of the photons and ##p_{photons}## is the 3 momentum of the photons. Rocket after engine switched off: $$P_{Final rocket} = (m_{f}c, m_{f}v)$$ By conservation of...