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2 years ago

We drive at a speed of 20 km/h for 3 hours. Then we drive 4 hours at 30 km/h. Calculate our average speed.

Physics

2 answers:

SashulF [63]2 years ago

6 0

Answer

A. T. Q

Total distance travelled by total time taken

<em><u>speed = Total distance / Total timeAverag</u></em><em><u>e</u></em>

Here Total distance travelled is 20 + 40 = 60 km by the car

total time taken is 1 + 3 = 4 hours

here the average speed of the car is given by

S=60/4=15km/hr

this is answer by the question

Afina-wow [57]2 years ago

4 0

First speed = 20km/h

Time = 3 hours

Distance = 3×20

Second speed = 30km/h

Time = 4 hours

Distance = 4×30

Total distance = 60+120 = <u>180km</u>

Total time = 3+4 =<u> 7 hours</u>

Average speed = 180/7

Hope this will help...

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Explanation:

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$I_{k_2} = I_{p_2} = m * r_f^2$

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$w_{k_2} =w_{p_2 } = w_2$

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