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Lerok [7]
4 years ago
8

A car initially traveling at 60 km/h accelerates at a constant rate of 2.0 m/s2. how much time is required for the car to reach

a speed of 90 km/h?4
Physics
1 answer:
bogdanovich [222]4 years ago
3 0
<span>since the car starts at 60 km/hr, first subtract the 60 from 90 km/hr which is 30. that is the acceleration we need to solve. 2.0 m/s multiply by 60 seconds in a minute, and 60 minutes in an hour, which equals 7200 m/s in an hour or divide by 1000 (1000 meters in a km) and have 7.2m an hour. divide the 30 km/hr by 7.2 and you have 4.167 hours. You could also take the 30 km/hr needed to accelerate to match the 90 km/hr and find the number of meters needed to accelerate which is 30,000. divide by 2 meters per second equals 15,000. divide by 60 seconds in a minute, and divide by 60 minutes in an hour which still equals 4.167 hours.</span>
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Answer:

8

Explanation:

Applying,

v = λf................ Equation 1

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f = v/λ............ Equation 2

From the question,

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If,

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Therefore,

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3 years ago
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katen-ka-za [31]

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Answer:

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