Explanation:
Friction occurs because no surface is perfectly smooth. Rougher surfaces have more friction between them. Heavier objects also have more friction because they press together with greater force. Friction produces heat because it causes the molecules on rubbing surfaces to move faster and have more energy.
The average speed between 0 h and 2.340 h is 6.97 Km/h
Average speed is defined as the total distance travelled divided by the total time taken to cover the distance.

With the above formula, we can obtain the average speed between 0 h and 2.340 h as illustrated below:
- Total time = 2.340 – 0 = 2.340 h
- Total distance = 16.3 – 0 = 16.3 Km
- Average speed =?

Learn more about average speed: brainly.com/question/24884027
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Answer: The nearest position of an object from a normal human eye so that its image is formed on retina is 25 CM. If the object is placed at a distance less than 25 CM, then the blurred image of the object is formed on retina as the focal length of a lens cannot be decreased below a certain limit. Hence we cannot see it clearly.
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