Respuesta :
Answer:
a) 26.47 miles
b) 138600 ft
c) 2.74 secs
d) 1.33 miles
Step-by-step explanation:
Rate of acceleration and deceleration = 10ft/s^2
Maximum cruising speed= 105 mi/h
Convert the cruising speed to ft/s
105*5280 / 3600
= 154 ft/s
15 mins = 15*60
= 900 secs
a) acceleration from rest = a(t)
a(t) = 10ft/s
Integrate a(t) to find v(t)
v(t) = 10t + C
Since v(0) = 0 , C = 0
V(t) = 10ft/s
To find s(t), integrate v(t)
s(t) = 10t^2/2 + C
s(t) = 5t^2 + C
When t= 0 , C = 0
s(t) = 5t^2
Time to get to maximum cruising speed = t
10t = 154
t = 154/10
t = 15.4 secs
Distance traveled with the acceleration time
s(15.4) = 5(15.4)^2
= 1185.8 ft
Maximum distance traveled = 900*154
= 138600ft
Total distance traveled = 1185.8 + 138600 =139785.8 ft
Convert to miles
139785.8/5280
= 26.47 miles
When s = 37.5
Recall that s(t) = 5t^2
37.5 = 5t^2
t^2 = 37.5/5
t^2 = 7.5
t = √7.5
t = 2.74 secs
When t = 37.5
s(37.5) = 5(37.5)^2
= 7031.25ft
Convert to miles
S= 7031.25/5280
s. = 1.33 miles