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2 years ago

11

A voltage of 21.0V across the terminals of a device produces a current of 3.00 mA through the device. What is the resistance of

the device?

1 answer:

densk [106]2 years ago

8 0

Answer: 7,000 ohms

Explanation:

From the equation of ohms law V= IR

V=21 volt

I = 3 MA = 3.0×10^-3 A

So by evaluating, we have.

V= IR

21= 3.0×10^-3 × R

Then R = 21/3.0×10^-3

R= 7,000 ohms//.

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The frequency of sound wave A is 250 Hz. Find the time period.

olga2289 [7]

Time period = 1 / frequency
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3 years ago

A metallic wire has a diameter of 4.12mm. When the current in the wire is 8.00A, the drift velocity is 5.40×10−5m/s.What is the

podryga [215]

Answer:

$6.9\times 10^{28}m^{-3}$

Explanation:

We are given that

Diameter of wire=d=4.12 mm

Radius of wire=r $r=\frac{d}{2}=\frac{4.12}{2}=2.06mm=2.06\times 10^{-3} m$

$1mm=10^{-3} m$

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Drift velocity= $v_d=5.4\times 10^{-5} m/s$

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We know that

Density of electron= $n=\frac{I}{v_deA}$

Using the formula

Density of free electrons= $\frac{8}{5.4\times 10^{-5}\times 1.6\times 10^{-19}\times 3.14\times (2.06\times 10^{-3})^2}$

By using Area of wire= $\pi r^2$

$\pi=3.14\\e=1.6\times 10^{-19} C$

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2 years ago

Read 2 more answers

a tire is rolling along a road, without slipping with a velocity v. a piece of tape is attached to the tire. When the tape is op

Kryger [21]

Answer:

The right solution will be the "2v".

Explanation:

For something like an object underneath pure rolling the speed at any point is calculated by:

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Although the angular velocity was indeed closely linked to either the transnational velocity throughout particular instance of pure rolling as:

⇒ $\omega=\frac{v_{translational}}{r}$

Significant meaning is obtained, as speeds are in the same direction. Therefore the speed of rotation becomes supplied by:

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On substituting the estimated values, we get

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⇒ $=v_{translational}$

So that the velocity will be:

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⇒ $=2v$

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2 years ago

Finish the sentence

Scrat [10]

The first blank is character
The last one is eye colour.

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2 years ago

A car traveling in a straight line has a velocity of 5.0 m/s. After an acceleration of 0.75 m/s/s, the cars velocity is 8.0. In

Bogdan [553]

Vs - velocity on beginning
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2 years ago