Question

a car takes 20 sec to travel . first 10 meters 20 minutes to travel next 40 km
find the average speed of the car

Answer 1

Given :-

• Time taken to travell first 10 m = 20s
• Time taken to travell next 40 km = 20 min

Conversion :-

Firstly converting all the same units (to m's & s)

40km → m

→ 40 × 10³

→ 40,000 m

20 min → s

→ 20 × 60

→ 1200 s

To find :-

• Average speed of the car

Solution :-

Firstly finding speed 1 (V1) & Speed 2 (V2)

Speed = distance/time

V1 = 10/20 = 0.5 m/s

V2 = 40000/1200 = 33.33 m/s

Now , finding average speed .

Average speed = 2V1V2/V1 + V2

Substituting the values of V1 & V2

→ Avg speed = 2(½)(33.33)/0.5 + 33.33

→ Avg speed = 33.33/33.8

→ Average speed = 1.01 m/s

Hence , average speed of car = 1.01 m/s

Answer 2

Answer:

Given:

★ A car takes 20 sec to travel. First 10 meters 20 minutes to travel next 40 km.

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To find:

★ Find the average speed of the car.

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Remember:

#To convert minutes to seconds we have to multiply min with cm.

#In the given question there are of two cases firstly let's find the speed of both cases and then apply the formulae.

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Using formulae:

★ Average speed = Distance covered/Time taken.

★ Speed of case 1 × case 2/Case 1 + Case ★

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Calculations:

★ Applying formulae we get for both the cases, we get:

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= 10/20

= 0.5 m/s

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Therefore, 0.5 m/s is the speed of car in the first case.

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★ Converting km to m and min to sec, we get:

• 40km × 1000 = 40,000 m.
• 20 × 60 = 1,200 sec.

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Adding values:

= 40000/1200

= 33.33 m/s

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Therefore, 33.33 m/s is the speed of car in the second case.

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Adding values from the before equations:

= 2 (1/2 × 33.33)/(0.5 + 33.33)

= 33.33/33.8

= 1.01 m/s

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Therefore, 1.01 m/s is the average speed of the car.