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ANEK [815]
4 years ago
15

An atom contains 15 neutrons and has a mass number of 30. What is its atomic number? How did you determine the atomic number?

Physics
1 answer:
irinina [24]4 years ago
8 0

Answer:

15

Explanation:

The mass number is defined as the total number of protons and neutrons. The atomic number is total number of protons. And since we have the mass number and number of neutrons, we can use simple subtraction (30 - 15) to find that the atomic number is 15.

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1) D

2) D.) Greater than \theta_c

Explanation:

1)

The phenomenon of total internal reflection occurs when a ray of light hitting the interface between two mediums is totally reflected back into the original medium, therefore no refraction into the second medium occurs.

This phenomenon occurs only if two conditions are satisfied:

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2)

As we stated in problem 1), total internal reflection occurs when the angle of incidence is equal or greater than the critical angle. Therefore in this case, the angle of incidence must be

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Two objects are placed in thermal contact and are allowed to come to equilibrium in isolation. The heat capacity of Object A is
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Answer:

Explanation:

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