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2 years ago

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25. Which of the following is true for an electromotor? A. It transforms thermal energy to electrical energy. B. It transforms m

echanical energy into electrical energy. C. It transforms electrical energy into mechanical energy. D. It transforms electrical energy into potential energy.

1 answer:

Vlad1618 [11]2 years ago

4 0

Answer:

C

Explanation:

it transforms electrical energy into mechanical energy.

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Here we will the speed of seagull which is v = 9 m/s

this is the speed of seagull when there is no effect of wind on it

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if effect of wind is in opposite direction then it travels 6 km in 20 min

so the average speed is given by the ratio of total distance and total time

$v_{avg} = \frac{6000}{20*60}$

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now since effect of wind is in opposite direction then we can say

$V_{net} = v_{bird} - v_{wind}$

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Part b)

now if bird travels in the same direction of wind then we will have

$v_{net}= v_{bird} + v_{wind}$

$v_{net} = 9 + 4 = 13 m/s$

now we can find the time to go back

$time = \frac{distance}{speed}$

$time = \frac{6000}{13}$

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Part c)

Total time of round trip when wind is present

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3 years ago

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Answer:

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To find the time we must use another kinematic equation.

$v_{f} =v_{i} +a*t\\replacing:\\33.33=0+(2.31*t)\\t=\frac{33.33}{2.31}\\ t=14.4[s]$

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3 years ago

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Answer:

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