Answer: option A. strong nuclear force.
Explanation:
The diagram shows the subatomic particles inside the nucelous: protons and neutrons.
As you know, the protons are positively charged partilces inside the nucleous.
Being those particles charged with the same kind of charge they experiment electrostatic repulsion. So, how do you explain that they can stand together in such small space as it is the nucleous?
The responsible of keeping the subatomic particles together is the so called strong nuclear force.
Strong nuclear force or simply strong force is one of the four fundamental interactions or forces: i) gravitational, ii) electromagnetic, iii) weak nuclear force, and iv) strong nuclear force.
Strong nuclear force is the strongest force of nature and acts only in short distances as those inside the nucleous and is responsible for both the atraction among quarks and the atraction among protons to bind them together inside the atomic nucleous.
        
             
        
        
        
Answer:

Explanation:
The gravitational force between the proton and the electron is given by

where
G is the gravitational constant
 is the proton mass
 is the electron mass
r = 3 m is the distance between the proton and the electron
Substituting numbers into the equation,

The electrical force between the proton and the electron is given by

where
k is the Coulomb constant
 is the elementary charge (charge of the proton and of the electron)
r = 3 m is the distance between the proton and the electron
Substituting numbers into the equation,

So, the ratio of the electrical force to the gravitational force is

So, we see that the electrical force is much larger than the gravitational force.
 
        
             
        
        
        
Answer:
-0.0789 m
Explanation:
Recall that the y-component comes associated with the sin(18.4) through the following trigonometric relationship:
y = 0.250 sin(-18.4) ≈ -0.0789 m
Notice it is negative since it is below the x-axis.
 
        
             
        
        
        
<span>
At the Earth's surface, warm air expands and rises, creating 
what is known as an area of low pressure.
 Cold air is dense and sinks to the surface to create what is 
known as an area of high pressure.</span>