Question

A truck traveling along a straight road at speed 20 km/hr, increases its speed to 120 km/hr in time 15s. If its acceleration is constant, determine the distance traveled.​

Answer 1

Answer: 291.68 m

Explanation:

Hi, to answer this question, first we have to calculate the acceleration:

Acceleration (a) = v2- v1 /t

Where: v1 =speed 1  

v2: speed2  

t = time (hours)

Since: 1 km/h = 1000/3600 m/s

v2= 120x 1000/3600 m/s = 33.3333 m/s

v1= 20 x 1000/3600 m/s =5.5556 m/s

Replacing with the values given:

a = 33.33-5.556 / 15 = 1.852 m/s^2

To find the distance:

d = v1 t + 1/2 a t^2 = 5.5556 m/s (15s) + 1/2 (1.852 m/s^2) 15s^2 =291.68 m