posted by Daniel on .
Realizing that she often doesn't have her students' full attention during class, a professor devises an elaborate device on which to stand while she lectures. The pulley is placed so that the string makes a 45.0-degree angle with the beam. The beam is uniform, 5.00 meters long, and has weight . The professor stands 2.00 meters from the pivot point and has weight .
If the professor's mass is 60 kilograms and the mass of the beam is 20 kilograms, what is the magnitude of the normal force exerted by the beam on the professor? Use 10 meters per second squared for the magnitude of the acceleration due to gravity.
Express your answer in newtons to two significant figures.