Well, let's assume you want to shoot a golf ball, which according to Google should weigh about 1.6 ounces. That's pretty light.
Adjusted for kilograms, a golf ball comes out at 0.0453592 kg. 50 percent the speed of light is 539,626,424 km/h (or about 540 million kilometers per hour), which when adjusted for m/s comes out to be 1.49896e8 meters per second. When all of the work is done, you'll get about 509,583,641,782,553.6 joules of energy for this golf ball's impact. This is enough to basically core any science fiction starship regardless of its armor or energy shielding. 1 joule is equal to 1 watt over 1 second. Assuming 100 percent efficiency, you'd need to dump about 510 trillion watts of electricity behind each shot in order to launch this golf ball at 0.50 percent of c. 1 trillion watts is equal to 1 terawatt. IIRC, humanity used about 16 TW of power back in 2006, which means you'd need to have a reactor that can produce 31 times the amount of power consumed by the entire human race during that particular year. And rapidly fill magical energy banks with this amount of juice (and discharge them without the entire ship exploding). And somehow cool this weapon (and its electrical components) down after each shot (and probably during the charging process too; unsure).
For one shot.
As I said, why haven't the Terrans conquered the galaxy yet?
WilsonTurner said
I can either warp for in-system FTL, which will pretty much make all combat capabilities useless and make scanning/radar unusable. And, ASTA, if you would have read and paid attention and not be so , you would realize that the Valkians primary defense will be armor, not shields or point defense. PD/Shield Clusters, maybe, but fighters will be more effective than missiles for taking those out.
You really can't detect sarcasm and/or jokes very well.