Question

Example 4 A car travelled the first half of its journey at 40 km/h and the next half at 60 km/h. Find the average speed of the car over the whole journey.​

Answer 1

Answer:

Explanation:

Given,

• Speed in the 1st half = 40 km/h
• Speed in the 2nd half = 60 km/h

To Find,

• Average Speed.

Formula to be used,

• Average speed = Total distance traveled/Total time taken

Solution,

Putting all the values, we get

Average speed = Total distance traveled/Total time taken

⇒ Average speed = 2x/(x/40 + x/60)

⇒ Average speed = 2x × 24/x

⇒ Average speed = 48x/x

⇒ Average speed = 48 km/h

Hence, the average speed of the car over the whole journey. is 48 km/h.

Answer 2

Answer:

• Average speed of car over the whole journey is 48 km/h.

Step-by-step explanation:

Given :-

• Speed of car in first half = 40 km/h
• Speed of car in second half = 60 km/h

To Find :-

• Average speed of car over the whole journey?

Solution :-

• Let total distance travelled by car be 2y km
• So, in both halfs distance travelled by car will be y km

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We know that,

• Time = Distance/Speed

Time taken by car in first half will be;

• T₁ = y/40 h

Time taken by car in second half will be;

• T₂ = y/60 h

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Again we know that,

• Average speed = (Total distance travelled)/(Total time taken)

We have,

• Total distance travelled = 2y km
• Total time taken = T₁ + T₂

Putting all values,

➙ Average speed = 2y/(T₁ + T₂)

➙ Average speed = 2y/(y/40 + y/60)

➙ Average speed = 2y/(6y/240 + 4y/240)

➙ Average speed = 2y/[(6y + 4y)/240]

➙ Average speed = 2y/10y/240

➙ Average speed = 2y/1y/240

➙ Average speed = 2y/y/24

We can write it as,

➙ Average speed = 2y ÷ y/24

➙ Average speed = 2y × 24/y

➙ Average speed = 2 × 24

➙ Average speed = 48 km/h

• Hence, average speed of car over the whole journey is 48 km/h.

Learn More :-

Related Questions:

1. Abdul, while driving to school, computes the average speed for his trip to be 20 km hl. On his return trip along the same route, there is less traffic and the average speed is 30 km h-!. What is the average speed for Abdul's trip?
2. If object moves with velocity of 5m/s,10m/s,15m/s in every 5 seconds then find average velocity?

Answer 1:

• brainly.in/question/43685797

Answer 2:

• brainly.in/question/46293383

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