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2 years ago

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A transformer is to be used to provide power for a computer drive. The number of turns in the primary is 1000, and it delivers a

secondary current of 600 milliamperes (mA) at a secondary voltage of 8.0 V for the drive. A voltage of 400 volts is applied across the primary. What kind of transformer is this?a. step upb. Loadc. Step-Downd. AC

1 answer:

Yuri [45]2 years ago

3 0

Answer:

C.Step-Down

Explanation:

Given that

Number of turn in the primary N₁= 1000

Secondary current I₂= 600 mA

Secondary voltage V₂= 8 V

Primary voltage V₁= 400 V

From the above information we can say that output voltage is low compare to input voltage.

V₂ < V₁

We know that if

1 . V₂ < V₁ - Then transformer will be step down .

2. V₂ > V₁ - Then transfer will be step up .

Here

V₂ < V₁ ( 8 V < 400 V)

So the transformer is step down transformer.

C.Step-Down

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Answer:

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Explanation:

Notice that we need to obtain a rotational frequency in "rpm" (revolutions per minute), so we better start by converting all the given information into the appropriate units:

The magnitude of the velocity for the pitch is given in miles per hour, while the diameter of the machine's wheels is given in cm. Let's reduce all units of length into meters(using the metric system), and the units of time into minutes.

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Recall that 1 mile equals 1609.34 meters, and that 1 hour equals 60 minutes, so we write:

$85\,\frac{miles}{hour} = 85\,\frac{1609.34\,m}{60\,min} =2279.898\,\frac{m}{min}$

which can be rounded to approximately 2280 m/min.

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diameter = 0.35 m

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but recall that this angular velocity is given in radians per unit of time. So first find the radius of the wheel (half its diameter). R = 0.175 m

So we have:

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2 years ago

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Summary:
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