A) 72.4 km
To calculate the total distance, we have to calculate the length of each part of the trip.
Part 1):
v = 50.0 km/h
t = 25.0 min = 0.42 h (25/60)
[tex]d_1 = vt=(50.0)(0.42)=21 km[/tex]
Part 2):
v = 95.0 km/h
t = 20.0 min = 0.33 h (40/60)
[tex]d_2 = vt=(95.0)(0.67)=31.4 km[/tex]
Part 3):
The woman stays constant for t = 40.0 min, so no distance covered in this part.
Part 4):
v = 40.0 km/h
t = 30.0 min = 0.5 h (30/60)
[tex]d_4 = vt=(40.0)(0.5)=20 km[/tex]
So the total distance covered is
[tex]d=d_1 +d_2+d_4=21+31.4+20=72.4 km[/tex]
B) 37.7 km/h
To find the average speed for the entire trip, we have to divide the total distance by the total time taken.
The total time taken is
[tex]t=25.0 + 20.0 +40.0 +30.0 =115.0 min[/tex]
Converted into hours,
[tex]t=\frac{115}{60}=1.92 h[/tex]
And the total distance is
d = 72.4 km
So the average speed is
[tex]v=\frac{d}{t}=\frac{72.4}{1.92}=37.7 km/h[/tex]
Answer:
Explanation:
We should know that
Speed = distance traveled/time taken
S= d/t
Then,
d = S×t
distance = speed × time
A woman drives in a city with different speed
1. She drives at
50km/hr for 25mins
Distance = speed × time.
Distance = 50km/hr × 25/60 he
Distance. = 20.833km
2. 95km/hr for 20mins
Distance = s × t
distance = 95km/hr × 20/60 hr
Distance = 31.667km
3. She stopped for 40mins, with traveling
t = 40mins.
4. She continue at 40km/hr for 30mins
Distance = speed × time
distance = 40km/hr × 30/60
Distance = 20km
A. Total distance travelled
We are going to add all the distance traveled from one point to another
Total distance = 20.833 +31.667+20
Total distance = 72.5 km
B. Average speed?
Average speed is the total distance divided by the total time taken, the time she used to stop will be added.
Total time taken is
T = 25 + 20 + 40 + 30
T = 115 mins
T = 115/60 = 1.917 hr
So,
Average speed = total distance / total time taken
A.S = 72.5 / 1.917
A.S = 37.83 km/hr
