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3 years ago

A young athlete has a mass of 42 kg. On a day when there is no wind she runs a 100m race in 14.2

Physics

1 answer:

Cloud [144]3 years ago

3 0

Answer:

7 m/s approx

Explanation:

Step one:

Given data

Mass m= 42kg

distance covered= 100m

time taken = 14.2 seconds

Required

The speed of the athlete

Step two:

We know that speed= distance/time

Substitute

Speed= 100/14.2

Speed= 7.04 m/s

Speed= 7 m/s approx

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3 years ago

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Alex, parked by the side of an east-west road, is watching car P, which is moving in a westerly direction. Barbara, driving east

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Answer:

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Now, for the velocity of Car p with respect to the velocity of Barbara's Car can be given s follows:

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