Answer:
a) d = 23.345 m : distance the car travels in the first second
b) d = 111.425 m : distance the car travels in the fifth second
Step-by-step explanation:
The distance (d) in uniformly accelerated motion is calculated as follows:
d = v₀*t +(1/2)*a*t² Formula (1)
d: distance (m)
v₀: initial speed (m/s)
a: acceleration (m/s²)
t: time (s)
Equivalences
1 km = 1000m
1 h = 3600 s
Data
v₀ = 85 km/h = 85*1000m/3600s = 23.61 m/s
a = - 0.53 m/s²
Calculation of the distance the car travels in the first second
We replace data in formula (1) at t = 1s
d = 23.61*(1)+ (1/2)*(-0.53)*(1)²
d = 23.345 m
Calculation of the distance the car travels in the fifth second
We replace data in formula (1) at t = 5s
d = 23.61*(5)+ (1/2)*(-0.53)*(5)²
d = 111.425 m