Newton's second law: A 60.0-kg person rides in an elevator while standing on a scale. The scale reads 400 N. The acceleration of the elevator is closest to A) 3.13 m/s² downward. B) 6.67 m/s² downward. C) zero. D) 9.80 m/s² downward. E) 6.67 m/s² upward.

Question

Quizplus · Accepted Answer

The scale reading represents the normal force acting on the person, which is less than the gravitational force (600 N) due to the person's weight (60.0 kg * 9.8 m/s^2). This indicates the elevator is accelerating downward. To find the acceleration, use Newton's second law: $F_{net} = ma$. The net force is the difference between gravitational force and the scale reading: $600 N - 400 N = 200 N$. Thus, $200 N = 60.0 kg * a$, solving for $a$ gives $a = 3.33 m/s^2$ downward. The closest answer provided is 3.13 m/s^2 downward.

Newton's Second Law: a 60