# electric charge and electric force

## electric force

When it comes to electric charges, opposites attract, so positive and negative particles attract each other. You can see this in the Figure 1.2. This attraction explains why negative electrons keep moving around the positive nucleus of the atom. Like charges, on the other hand, repel each other, so two positive or two negative charges push apart. This is also shown in the diagram. The attraction or repulsion between charged particles is called electric force. The strength of electric force depends on the amount of electric charge on the particles and the distance between them. Larger charges or shorter distances result in greater force. Q: How do positive protons stay close together inside the nucleus of the atom if like charges repel each other? A: Other, stronger forces in the nucleus hold the protons together.

## introducing electric charge

Electric charge is a physical property of particles or objects that causes them to attract or repel each other without touching. All electric charge is based on the protons and electrons in atoms. A proton has a positive electric charge, and an electron has a negative electric charge. In the Figure 1.1, you can see that positively charged protons (+) are located in the nucleus of the atom, while negatively charged electrons (-) move around the nucleus.

## instructional diagrams

No diagram descriptions associated with this lesson

## questions

electric charge is a physical property of matter.

``````-->  a. true

b. false
``````

charged particles must touch in order to attract or repel each other.

``````a. true

-->  b. false
``````

all electric charge is based on protons and neutrons.

``````a. true

-->  b. false
``````

for which pair of particles is there electric attraction between particles?

``````a) proton and proton

b) electron and electron

-->  c) electron and proton

d) two of the above
``````

for which pair of particles is there electric repulsion between particles?

``````a) proton and neutron

b) electron and neutron

c) electron and proton

-->  d) none of the above
``````

the strength of electric force between two charged particles depends on the

``````a) amount of electric charge on the particles.

b) distance between the charged particles.

c) magnetic force between the charged particles.

-->  d) two of the above
``````

## diagram questions

No diagram questions associated with this lesson