World-class sprinters can accelerate out of the starting blocks with an acceleration that is nearly horizontal and has magnitude 15 m/s2. How much horizontal force must a 55 kg sprinter exert on the starting blocks to produce this acceleration? which object exerts the force that propels the sprinter: the blocks or the sprinter herself?

Which of the following would be considered a nec code violation in regards to the installation of luminaires? a. an outdoor lighting fixture mounted to a tree b. a five-pound, 12-inch diameter light fixture supported by the screw shell of the lampholder c. florescent lay-in fixtures attached to the framing sections of a suspended ceiling with sheet-metal screws d. track lighting over a sink, 2 feet from a bathtub