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3 years ago

A jogger runs 6 km north ,5 km east then another 4km north her average speed 8 km how long will it take her to complete her run

Physics

1 answer:

LekaFEV [45]3 years ago

8 0

The time taken to complete her run is 1.9 hr.

<u>Explanation:</u>

Speed is a scalar quantity and it is defined as the ratio of distance covered to the time taken to cover that distance. As distance is also a scalar quantity, so the directions given in the problem can be ignored. Thus, the distance covered by the jogger is the sum of kilometers given in problem.

Distance covered = 6+5+4 = 15 km

And the speed is given as 8 km/hr.

So the time taken will be ratio of distance to speed.

$\text { time }=\frac{\text {distance}}{\text {speed}}=\frac{15}{8}=1.9 \text { hour }$

So the jogger will take 1.9 hr to complete her run.

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➤ Although your question isn't complete, I may have assumed that you were referring to this specific question.

The complete question is :

A TMS (transcranial magnetic stimulation) device creates very rapidly changing magnetic fields. The field near a typical pulsed-field machine rises from 0 T to 2.5 T in 200 μs. Suppose a technician holds his hand near the device so that the axis of his 2.1-cm-diameter wedding band is parallel to the field.

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