Sagot :
Answer:
a) v = 0.515 km / min , b) x_total = 52 km
Explanation:
The measured speed is defined by the distance traveled between the time
v = [tex]\frac{\Delta x}{\Delta t}[/tex]
In this case they give us the speed in several time intervals
let's find the distance traveled in each interval
a) Goes at 75 km/h for 10 min
v = [tex]\frac{x}{t}[/tex]x / t
x₁ = v t
let's reduce speed to km / min
v₁ = 75 km / h (1h / 60 min) = 1.25 km / min
the distance traveled in this time is
x₁ = 1.25 10
x₁ = 12.5 km
b) goes to v = 95 km / h for 6 min
v = 95 km / h (1h 60 min) = 1.5833 km / min
the distance traveled is
x₂ = v₂2 t
x₂ = 1.58333 6
x₂ = 9.5 km
c) goes to v = 40 km / h for 45.0 min
v₃ = 40 km / h (1 h / 60min) = 0.6667 km / min
x₃ = 0.6667 45
x₃ = 30 km
d) t = 40 min, stopped
x₄ = 0
A) let's calculate the average speed of the trip
v =[tex]\frac{x_{1}+x_{2}+x_{3}+x_{4} }{t_{1}+t_{2}+t_{3}+t_{4} }[/tex]
v = (12.5 +9.5 +30 +0) / (10 +6 +45 +40)
v = 52/101
v = 0.515 km / min
B) the distance between the two cities is
x_total = x₁ + x₂ + x₃
x_total = 12.5 +9.5 + 30
x_total = 52 km