Question

 A car travelling along a straight path, covers 50 km with the velocity of 25 km/h, and then 60 km with a velocity of 20 km/h. Find the average speed of the car​

Answer 1

Let us understand this by the diagram

⠀⠀⠀25km/hr ⠀⠀⠀⠀20km/hr⠀⠀⠀⠀⠀⠀

⟨━━━━━━━━━|━━━━━━━━━━━⟩

⠀⠀⠀⠀50 km ⠀⠀⠀⠀⠀⠀60 km⠀⠀⠀⠀⠀⠀

Given :-

• Distance (S₁) = 50 km
• Distance (S₂) = 60 km
• Speed (V₁) = 25 km/hr
• Speed (V₂) = 20 km/hr

Therefore, Calculating Time (T)

$\implies \bf T = \dfrac{s_{1}}{v_{1}} + \dfrac{s_{2}}{v_{2}}$

Substituting Values

$\implies \sf T = \cancel{ \dfrac{50}{25}} + \cancel{\dfrac{60}{20}}$

$\implies \sf 2 + 3$

$\implies \sf 5$

Thus, the time taken for the car to complete it all is 5 hrs.

Now, Calculating Average Speed

$\bf Average \: Speed = \dfrac{Total \: Distance (S)}{Total \: Time(T)}$

$\implies \sf \dfrac{50+60}{5}$

$\implies \sf \dfrac{110}{5}$

$\implies \sf 22$

Therefore, the average speed of the car is 22 km/hr.

Answer 2

Aɴsᴡᴇʀ:

• The average speed of the car = 22 km/hour

Gɪᴠᴇɴ:

• A car travelling along a straight path, covers 50 km with the velocity of 25 km/h, and then 60 km with a velocity of 20 km/h.

Nᴇᴇᴅ ᴛᴏ ғɪɴᴅ:

• The average speed of the car = ?

Solution:

♲︎︎︎ In Case 1:

• Calculate the Time = ?

Fᴏʀᴍᴜʟᴀ ᴜsᴇᴅ ʜᴇʀᴇ:

• Time = $\sf {s_1 / v_1}$ + $\sf {s_2 / v_2}$

Pᴜᴛᴛɪɴɢ ᴛʜᴇ ᴠᴀʟᴜᴇs:

➦ Time = 50/25 + 60/20

➦ Time = 2 + 3

➦ Time = 5 hours

Tʜᴇʀᴇғᴏʀᴇ:

• Time taken is 5 hours.

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬

♲︎︎︎ In Case 2:

• The average speed of the car = ?

Fᴏʀᴍᴜʟᴀ ᴜsᴇᴅ ʜᴇʀᴇ:

• Average speed = Total distance/Taken time

Pᴜᴛᴛɪɴɢ ᴛʜᴇ ᴠᴀʟᴜᴇs:

➦ Average speed = 50 + 60/5

➦ Average speed = 110/5

➦ Average speed = 22 km/hour

Tʜᴇʀᴇғᴏʀᴇ:

• The average speed of the car is 22 km/hour.

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬