Momentum attained by a laser beam

[jstrike]

A small spaceship, with a mass of 1500 kg (including occupants), is at rest in outer space with negligible gravitational forces acting on it. If the astronaut turns on a 10kW laser beam that points out of the ship into the deep of space, what speed will the ship attain in 1 day because of the momentum carried away by the beam?

W=J/s
10000W=10000J/s
10000*60*60*24= 864000000J
864000000=.5*1500v^2
v= 1073.31

where do i go from here?

 

[mgb_phys]

What's the equation for the momentum of a photon and it's energy.
How many photons/second of this momentum can you generate from this laser power

 

[Ikoro]

E=pc
p= h/ lamda
E= hc/ frequency
play with these formulas by sub. then you should get it.. by the way the p=momentum