I need a lot of help with Coulomb's Law and Electric Fields? Need HELP

[devilz_krypt]

I need a lot of help with Coulomb's Law and Electric Fields?? Need HELP!

Homework Statement

Here are 3 of the 25 questions the i did not understand, in regards with electric fields and Coulomb's Law.

1. A small object of mass 2.0 g and charge of 1.8x10^-7 C "floats" in an electric field. Find the magnitude and direction of the field.

2. An electron is accelerated by a constant electric field of magnitude 300 N/C.
A) Find the acceleration of the electron.
B) How far will the electron travel in 3s?

3. Two charges lie along the x-axis. If q1= -9.0x10^-6 C is at x= 6m and q2= -8x10^-6 C at x= -4m, locate the point at which the electric field will be zero.

Please help me finish my test review, i have been very confused ever since we start Coulomb's Law and Electric Fields.

Homework Equations

F= ((k)(q1)(q2))/(r^2)
E= (k)(q)/(r^2)
F= qE

The reason I didnt submit my solution is because i have about 5 different solutions for each problem.

 

[Kurdt]

Submit the solution you think is best for each one.

 

[nlightner]

I understand that Coulomb's Law and Electric Fields can be challenging concepts to grasp. It is important to remember that these concepts are fundamental to understanding electricity and are used in many applications, such as electronics and power generation.

In order to better understand Coulomb's Law and Electric Fields, it is important to review the equations and principles involved. Coulomb's Law 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. This can be represented by the equation F= (k)(q1)(q2)/(r^2), where k is the Coulomb's constant, q1 and q2 are the charges of the objects, and r is the distance between them.

Electric Fields, on the other hand, are defined as the force per unit charge that a test charge experiences at a given point in space. The equation for Electric Fields is E= (k)(q)/(r^2), where q is the test charge and r is the distance from the source charge.

Now, let's address the questions you have listed.

1. In order to find the magnitude and direction of the electric field in this problem, we can use the equation E= (k)(q)/(r^2). Since the object is "floating" in the field, we know that the net force on the object is zero. This means that the force due to gravity must be equal and opposite to the force due to the electric field. We can set up the equation Fg= Fe and solve for the electric field (E). Plugging in the values given, we get E= (6.67x10^-11 N*m^2/C^2)(1.8x10^-7 C)/(2.0x10^-3 kg)^2. This gives us an electric field of 1.5x10^4 N/C directed towards the positive charge.

2. A) To find the acceleration of the electron, we can use the equation F= qE. Since the electron has a charge of -1.6x10^-19 C, we can plug this into the equation along with the given electric field of 300 N/C. This gives us a force of -4.8x10^-17 N. Using Newton's second law (F=ma), we can solve for the acceleration (a). This gives us an acceleration of -3.