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makvit [3.9K]
3 years ago
14

A train travels 98 kilometers in 1 hours, and then 78 kilometers in 3 hours. what is its average speed?

Physics
1 answer:
ozzi3 years ago
7 0

The average speed over the total four hour interval is

\dfrac{98\,\mathrm{km}+78\,\mathrm{km}}{4\,\mathrm h}=31\,\dfrac{\mathrm{km}}{\mathrm h}

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Answer:

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Solution:

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For the current to be the same when the switch is open or closed, the resistances must be connected in parallel as current is distributed in parallel with the same voltage across the circuit:

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