Respuesta :
Answer:
The total distance covered by the car is 3,810.08 m
Explanation:
Given;
initial speed of the car, u = 72 km/hr = 20 m/s
initial time, t₁ = 15 minutes = 900 s
final speed of the car, v = 80 km/hr = 22.22 m/s
final time, t₂ = 12 minutes = 720 s
The acceleration of the car is given as;
[tex]a = \frac{v-u}{t_2 -t_1} \\\\a = \frac{22.22-20}{900-720}\\\\a = 0.0123 \ m/s^2[/tex]
The total distance covered by the car is given as;
v² = u² + 2as
where;
s is the total distance covered by the car
22.22² = 20² + 2(0.0123)s
22.22² - 20² = 2(0.0123)s
93.728 = 0.0246s
s = 93.728 / 0.0246
s = 3,810.08 m
Therefore, the total distance covered by the car is 3,810.08 m
Answer:
34 km
Explanation:
Remark
You are dealing with distance not direction. So you just figure out the two parts separately and add.
15 minutes
t = 15 minutes * 1 hour / 60 minutes = 0.25 hours.
r = 72 km / hr
d = 72 km / hr * 0.25 hours
d = 18 km
12 minutes
t = 12 minutes * 1 hour/ 60 minutes = 0.2 hours
r = 80 km/hour
d = 80 * 0.2 = 16 km
Total distance
d = d1 + d2
d = 18 + 16 = 34 km