A body is traveling at 18.0 m/s and comes to rest after undergoing a uniform negative acceleration for 40.0 m.

a) What is the acceleration of this body?

b) How long does it take to come to rest?

A 72-kg man stands on a spring scale in an elevator. Starting from rest, the elevator ascends, attaining its maximum speed of 1.2 m/s in 0.80 s. The elevator travels with this constant speed for 5.0 s, undergoes a uniform negative acceleration for 1.5 s, and then comes to rest. What does the spring scale register:

(a) Before the elevator starts to move?

(b) During the first 0.80 s of the elevator’s ascent?

(c) While the elevator is traveling at a constant speed?

(d) During the elevator’s negative acceleration?

A 72-kg man stands on a spring scale in an elevator. Starting from rest, the elevator ascends, attaining its maximum speed of 1.2 m/s in 0.80 s. The elevator travels with this constant speed for 5.0 s, undergoes a uniform negative acceleration for 1.5 s, and then comes to rest. What does the spring scale register (a) before the elevator starts to move? (b) During the first 0.80 s of the elevator’s ascent? (c) While the elevator is traveling at constant speed? (d) During the elevator’s negative acceleration?

A 83-kg man stands on a springscale in an elevator. Starting fromrest, the elevator ascends,attaining its maximum speed of 1.2 m/sin 0.93 s. The elevator travels with thisconstant speed for 5.0 s,undergoes auniform negative accelerationfor 1.8 s, andthen comes torest. What does the spring scale register in each ofthe followingtime intervals?