Physics, asked by salafikhaliq166, 4 months ago

A car goes town A to another toen B with a speed of 40km/h and return back to the town A with speed of 60km/h the average speed of car during the complete journey is what​

Answers

Answered by ashutoshghosh319
4

Answer:

48 km/hr

Explanation:

In such types of questions we have to understand that the time taken in both the parts of the journey are not the same. Let distance between town A and B be x km.

While going:

Time taken = Total distance / speed.

= (x km) / (40 km/hr)

While returning:

Time taken = (x km) / (60 km/hr)

Average speed = Total distance/ Total time

(x km + x km) /{(x km) / (40 km/hr) + (x km) / (60 km/hr)}

= 2x / (3x + 2x / 120)

= 2x / (5x/120)

= 2x / (x/24)

= (2x × 24)/ x

= 48 km/h

Answered by snehitha2
6

Answer:

The average speed of the car during the complete journey is 48 km/h

Explanation:

Given :

A car goes town A to another town B with a speed of 40 km/h and return back to the town A with speed of 60 km/h

To find :

the average speed of car during the complete journey

Solution :

Let the distance between town A and town B be 'x km'

Town A to Town B :

speed = 40 km/h

distance = x km

time taken = ?

Speed = distance/time taken

40 km/h = x km/ time taken

time taken = x/40 hr

Town B to Town A :

speed = 60 km/h

distance = x km

time taken = ?

Speed = distance/time taken

60 km/h = x km/time taken

time taken = x/60 hr

Average speed :

Total distance covered = x + x = 2x km

total time taken = x/40 + x/60

Average speed = total distance covered/total time taken

 \longrightarrow \sf \dfrac{2x}{\dfrac{x}{40} +\dfrac{x}{60}} \\\\\\ \longrightarrow \sf \dfrac{2}{\dfrac{1}{20}\bigg(\dfrac{1}{2}+\dfrac{1}{3} \bigg)} \\\\\\ \longrightarrow \sf \dfrac{2 \times 20}{\dfrac{3+2}{6}} \\\\\\ \longrightarrow \sf \dfrac{40}{\dfrac{5}{6}} \\\\\\ \longrightarrow \sf \dfrac{40 \times 6}{5} \\\\ \longrightarrow \sf \dfrac{240}{5} \\\\ \longrightarrow \sf 48 km/h

Therefore, the average speed of the car during the complete journey is 48 km/h

Similar questions