physics puzzles

If a spaceship traveled at 1/10th the speed of light for 40 years, how much time would have passed on Earth during that same time? Thanks

Not really. But I read in this article that NASA are perfectly happy to let 550kg of satellite fall randomly to the earth. They calculate odds of hitting someone at 3200 to 1. This seems a little too probable to me. For some reason it reminded me of the perils of celebratory gunfire. What...

A couple physics brainteasers have been being tossed around over on the "classic physics" thread. One involves a 'light tight' caboose and the ability/inability to determine direction of travel. Here's a related one that may involve a little specific knowledge related to soaring flight but may...

So, I was reading about this guy Alexander Diem who set a skydiving speed record of 313mph. But nowhere did it tell me how long he spent in freefall. I calculated as follows. 313mph *5280 = 1,652,640 feet per hour /60, /60 = 459.0667 feet per second So, I hear that falling bodies...

A converging lens has a focal length of 10 cm. A screen is placed 30 cm from an object. Where should the lens be placed, in relation to the object, to produce a focused image? You're supposed to be able to get the answer using the thin lens equation, F = 10cm di + do = 30cm 1/di + 1/do = 1/F...

I'm not terribly good at math, so I need help with a comparision of two different kinematic systems, please. It's been puzzling me. There are two chains at the very edges of two different precipices. Each chain is 1000 meters long. Chain A is just over a 1000 meter drop. Chain B is just over...

If you’re in outer space traveling in a spaceship at the speed of light, and theoretically, if you could stick a gun out the window and fire a bullet that travels at 265 feet per second, how long would it take the spaceship to pass the bullet? I said the bullet would never leave the barrel...