A 20-car train standing on the siding is started in motion by the train’s engine. 2 cm slack is between each of the cars, which are 11 m long. The engine is tightly connected to the first car and moves at a constant speed of 21 cm/s. How much time is required for the pulse to travel the length of the train? Answer in units of s.

1.81 s

Explanation:

From the given information:

The links between the cars are:

1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10, 10-11, 11-12, 12-13, 13-14, 14-15, 15-16, 16-17, 17-18, 18-19, 19-20.

where;

1 denotes the first car that joins strongly attached to the engine.

There are 19 links from the above connections and each one of them has a 2 cm slack.

Thus; the total slack = 2 × 19 = 38 cm

However, the speed of the train = 21 cm/s

Then, the time taken by the pulse to travel the length of the train is expressed by using the formula:

= length / speed

= 38 / 21

= 1.81 seconds

Thus, the required time = 1.81 s

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in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..