Final answer:
The total mass of the dictionary and Fernando is 49.6 kg. The normal force exerted by the table on the dictionary is calculated using the weight equation and is 486.08 N, acting upward.
Step-by-step explanation:
Fernando places a 1.60-kg dictionary on a tabletop and then sits on top of the dictionary, with his own mass being 48.0 kg. The question is to find the normal force exerted by the table on the dictionary.
To solve this, we first need to calculate the total mass resting on the table, which would be the mass of the dictionary plus Fernando's mass. This gives us a total mass m of 1.60 kg + 48.0 kg = 49.6 kg. Since the dictionary and Fernando are at rest, the normal force exerted by the table must balance the gravitational force acting on them.
The gravitational force (weight) can be calculated using the equation W = m × g, where g is the acceleration due to gravity (9.80 m/s²). Therefore, the weight W is 49.6 kg × 9.80 m/s², resulting in W = 486.08 N. This weight is the force that the table must exert upward to support the dictionary and Fernando, which means the normal force N is also 486.08 N, and since it acts upward, it is a positive value.
Thus, the normal force exerted by the table on the dictionary is 486.08 N.