Answer:
0.799km
Step-by-step explanation:
First we need to get the acceleration diring the first part of the journey. According to equation of motion, v² = u² + 2as where;
v is the final velocity = 160km/hr
= 160000/3600 = 44.4m/s
u is the initial velocity = 0km/hr = 0m/s
S is the distance covered= 0.4km = 400m
44.4² = 0² + 2(400)a
1971.36 = 800a
a = 1971.36/800
a = 2.46m/s²
Since the car accelerates for 2.46m/s² during the first part of the journey, we can get the time taken by the car during this period using
v = u + at
44.4 = 0 + 2.46t
t = 44.4/2.46
t = 18seconds
Displacement if the car during this period will be gotten using the formula change in velocity = displacement/time
Displacement = change in velocity×time = 44.4 × 18 = 799.2m
= 0.799km