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NikAS [45]
2 years ago
7

You normally drive a 12-h trip at an average speed of 100 km/h . Today you are in a hurry. During the first two-thirds of the di

stance, you drive at 116 km/h
If the trip still takes 12 h, what is your average speed in the last third of the distance?
Physics
1 answer:
kherson [118]2 years ago
8 0

Answer:

78 km/h

Explanation:

If I normally drive a 12 hour trip at an average speed of 100 km/h, my destination has a total distance of:

  • 100 km/h · 12 h = 1,200 km

Today, I drive the first 2/3 of the distance at 116 km/h. Let's first calculate what 2/3 of the normal distance is.

  • 1,200 * 2/3 = 800 km

I've driven 800 km already. I need to drive 400 km more to reach my final destination. I need to figure out my average speed during this last 1/3 of the distance.

To do this, I first need to calculate how much time I spent driving 116 km/h for the past 800 km.

  • 116 km/1 h = 800 km/? h
  • 800 = 116 · ?
  • ? = 800/116
  • ? = 6.89655172

I spent 6.89655172 hours driving during the first 2/3 of the distance.

Now, I need to subtract this value from 12 hours to find the remaining time I have left.

  • 12 h - 6.89655172 h = 5.10344828 h  

Using this remaining time and my remaining distance, I can calculate my average speed.

  • ? km/1 hr = 400 km/5.10344828 h
  • 5.10344828 · ? = 400
  • ? = 400/5.10344828
  • ? = 78.3783783148  

My average speed during the last third of the distance is around 78 km/h.

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From the question we are told that

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Generally the equation of speed of rocket v mathematically given by

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where

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\triangle t=\frac{36}{(\sqrt{1-860/ \triangle t)^2}}

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b)

Generally the equation of the energy E required to attain prior speed mathematically given by

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E=7.566*10^{22}

c)Generally the equation of the energy E_a required to accelerate the rocket mathematically given by

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