1. A steady current 1.5 amps flows in a wire out of the page. A small +4 uc point charge is 5 can away from wire and moving towards at 3000 m/s? What is the magnetic force acting in the charge?
2. Some people can detect as few as 100 photons per second for green light, 545 nm. What is the power delivered by that beam if light?
3. How long does it take red light 700nm to travel 10m in water? N=1.33