Question

A train started from rest and moved with constant acceleration. At one time it was traveling 27 m/s, and 150 m farther on it was traveling 54 m/s. Calculate (a) the acceleration, (b) the time required to travel the 150 m mentioned, (c) the time required to attain the speed of 27 m/s, and (d) the distance moved from rest to the time the train had a speed of 27 m/s.

Answer 1

Step-by-step explanation:

A)

vf² = vi² + 2(a)(d)

(54 m/s)² = (27 m/s)² + 2(a)(120 m)

a = 9.1125 m/s²

a = 9.1 m/s²

B)

d = (vi)(t) + (1/2)(a)(t²)

150 m = 0 + (1/2)(9.1125)(t²)

t = 5.7 s

C)

vf = vi + (a)(t)

27 m/s = 0 + (9.1125)(t)

t = 3.0 s

D)

d = (vi)(t) + (1/2)(a)(t²)

d = 0 + (1/2)(9.1125)(2.96²)

d = 40 m