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alex41 [277]
3 years ago
6

How many neutrons does element X have if its atomic number is 39 and its mass number is 79?

Physics
1 answer:
bazaltina [42]3 years ago
6 0

Number of neutrons: atomic mass - atomic number

Element X's atomic mass is 79 and its atomic number is 39. Subtract 39 from 79 to find how many neutrons Element X has.

79 - 39 = 40

Element X has 40 neutrons.

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Answer:

Intensity, I=1.101\ W/m^2

Explanation:

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I=\dfrac{P}{A}

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I=1.101\ W/m^2

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A capacitor consists of two metal surfaces separated by an insulating layer. A new capacitor has no charge on either of its surf
mihalych1998 [28]
<h2>Answer:</h2><h3>(A) the positively charged surface increases and the energy stored in the capacitor increases.</h3>

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On the other hand, the potential energy U can be expressed as:

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Answer:

Simple harmonic motion is repetitive. The period T is the time it takes the object to complete one oscillation and return to the starting position. ... If at t = 0 the object has its maximum displacement in the positive x-direction, then φ = 0, if it has its maximum displacement in the negative x-direction, then φ = π.

Explanation:

Simple harmonic motion, in physics, repetitive movement back and forth through an equilibrium, or central, position, so that the maximum displacement on one side of this position is equal to the maximum displacement on the other side

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