A60.0-kg person rides in elevator while standing on a scale. the elevator is traveling downward butslowing down at a rate of 2.00 m/s2. the reading on the scale is closest toa) 589 n. b) 708 n. c) 469 n. d) 120 n.

C) 469 N

Explanation:

The reading on the scale corresponds to the normal reaction exerted by the scale on the person, R.

There are two forces acting on the person:

- Its weight (acting downward), equal to , where m = 60 kg is the mass of the person and g = 9.81 m/s^2 is the acceleration due to gravity

- The normal reaction of the scale, R, acting upward

According to Newton's second law, the resultant of these two forces must be equal to the product between mass and acceleration:

where we know that since the elevator is traveling downward at 2.00 m/s^2. Solving the equation for R, we find

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west