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Valentin [98]
3 years ago
12

All atoms of the element potassium have 19 protons. One of the most stable types of potassium atoms has the mass number 39. How

many neutrons make up one of these potassium atoms?
A. 19
B. 29
C. 38
D. 58
Physics
2 answers:
nydimaria [60]3 years ago
7 0
For atoms in the periodic table, the given mass number is the sum of the number of the protons (also called the atomic number) and the number of the neutrons inside its nucleus. Mathematically,
                              mass number = atomic number + number of neutrons
Substituting,
                               39 = 19  + n
                                    n = 39 - 19 = 20
Therefore, the answer is not found in the choices. 
steposvetlana [31]3 years ago
4 0

Answer:

N = 20

Explanation:

As we know that mass number is the sum of number of protons and number of neutrons present in the atom

So we will have

mass number A = 39

number of protons in the given atom (Z) = 19

so we will have

A = Z + N

39 = 19 + N

N = 20

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Light shined through a single slit will produce a diffraction pattern. Green light (565 nm) is shined on a slit with width 0.210
kondor19780726 [428]

Answer:(a)9.685 mm

(b)4.184 mm

Explanation:

Given

Wavelength of light (\lambda )=565nm \approx 565\times 10^{-9}m

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(a)Width of central maximum located 1.80m from slit

=\frac{2\lambda L}{b}

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5 0
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Anni [7]

Answer:

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force for moving constant velocity 2.25 N

Explanation:

given data

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static coefficient of friction = 0.10

solution

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weight of block of ice = mass  ×  g

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so here Ff = Fa

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and

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7 0
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Answer:

following are the solution to this question:

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