Question about electric force.

In summary, the question is asking about the magnitude of electric force between two charged corks, one with a charge of +5.0C and the other with a charge of -3.1C. The force can be calculated using the Coulomb constant and the distance between the corks. The force is attractive, as indicated by the negative sign in the equation. The negative cork has an excess of electrons, while the positive cork has lost some electrons. The fundamental charge of an electron can be used to determine the number of excess electrons on the negative cork. To solve for the number of electrons lost by the positive cork, more information is needed.
  • #1
donjt81
71
0
This is a four part question

Q1> A small cork with an excess charge of +5.o C is placed 0.10m from another cork, which carries a charge of -3.1C. The Coulomb constant is given. What is the magnitude of electric force between the corks.

A1> I will be using F = kq1q2/R-squared. The only thing that is throwing me off is... why would the question say excess charge and not just charge. any comments?

Q2> is this force attractive or repulsive
A2> attractive ofcourse

Q3>Now this is the part that I am having trouble with.
How many excess electrons are on the negative cork?
A3> Is there some fundamental idea that I am missing here? I don't know how to do this part.

Q4>How many electrons has the positive cork lost?
A4> don't know this one either. Maybe this will become more evident after I know how to solve Q3.

Can anyone help please.

Thanks in advance
 
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  • #2
do you know the fundamental charge of the electron?
 
  • #3
donjt81 said:
This is a four part question

A1> I will be using F = kq1q2/R-squared. The only thing that is throwing me off is... why would the question say excess charge and not just charge. any comments?

When an object has positive charge that means that there are more positive charges than negative ones. If it's negativly charged then it has more negative charged particles (electrons) than positive ones. If the amount is equal then it has a neutral charge.
 
  • #4
ohhh ok.

In my book I have 1e = this much C (charge) ... i don't remember the number exactly but I can look it up in my book.

So for question 3 all i need to do is take the charge of q1 which is given to be +5C and divide it by the charge in 1e and that will give me the answer. Thanks andrewchang. Can you confirm my reasoning above.

So what am I missing in question 4. How would I approch Q4.

PS Daniel thanks for that explanation on positive and negative charge.
 

1. What is electric force?

Electric force is a physical phenomenon that is generated by the interaction between charged particles. It is also known as electrostatic force and is responsible for the attraction or repulsion between two charged objects.

2. How is electric force calculated?

Electric force is calculated using Coulomb's law, which states that the force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

3. What are the units of electric force?

The SI unit of electric force is Newton (N). However, it can also be expressed in other units such as Coulomb (C), volt (V), and ampere (A).

4. What are some real-life applications of electric force?

Electric force has numerous applications in our daily lives, such as in the functioning of electronic devices, electricity generation and transmission, and even in the human body (e.g. nerve impulses and muscle contractions).

5. How does electric force differ from gravitational force?

Electric force and gravitational force are both fundamental forces of nature, but they differ in several ways. Electric force is much stronger than gravitational force, and it can be either attractive or repulsive, while gravitational force is always attractive. Additionally, electric force acts between charged particles, while gravitational force acts between any two objects with mass.

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