A world-class tennis player can serve a tennis ball at 110 mi/h (about 49 m/s ). The length of a tennis court is 78 ft . Approximately how long does an opponent have to react from the instant the ball is served until the ball reaches the opponent?

What would be the result of an alpha particle coming into a magnetic field? a) the alpha particle will stop moving. b) the alpha particle will reverse its direction. c) the alpha particle will be deflected in a curve path. d) the alpha particle will continue to travel in a straight line.