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3 years ago

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A 2000 kg car, initially at rest, is accelerated along a horizontal roadway at 3 m/s2. What is the average power required to bri

ng the car to a final speed of 20 m/s?

1 answer:

FromTheMoon [43]3 years ago

5 0

Answer:

Power = 120000 watts

Step-by-step explanation:

mass = 2000kg

acceleration = 3m/s²

velocity = 20m/s

Force = mass x acceleration

Force = 2000 x 3 = 6000 Newton

Power = Force x velocity

Power = 6000 x 20 = 120000 watts

Since 1000 watts = 1kilo-watts

Power = 120000 watts or 120 kilo-watts

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99% confidence level

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$0.04 = 2.575\sqrt{\frac{0.5*0.5}{n}}$

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$0.04 = 2.575\sqrt{\frac{0.55*0.45}{n}}$

$0.04\sqrt{n} = 2.575*\sqrt{0.55*0.45}$

$(\sqrt{n}) = \frac{2.575*\sqrt{0.55*0.45}}{0.04}$

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Rounding up

n = 1026.

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