Purchase Solution

# Electric Fields and Electric Potential

Not what you're looking for?

Four quick conceptual questions:

1) Is the electric field (E = -delta V / delta s) always a positive number (or zero)? That is, is it always the absolute value of the magnitude of the electric field? Or can it have a negative value?

2) Is electric potential (delta V) always negative? The answer to one of the questions in my book says: 'the negative value of delta V in this question simply indicates that the electric potential of the negative plate is less than that of the positive plate.' This seems to imply that electric potential is always negative.

3) My book gives this equation for electric potential energy:
delta U =(q)(delta V)=(q)(E)(d)
but if delta V = (-E)(delta s),
shouldn't delta U = (q)(-E)(d)?

4) Also, can you give a quick explanation of what exactly electric potential is, and how it relates to electric potential energy?

Thank you!

##### Solution Summary

The solution carefully explains each of the four conceptual questions posed in the subject of electric fields and potentials, drawing on relevant equations to give a fuller understanding.

##### Solution Preview

1) Electric field is a vector quantity, i.e., it has a direction and some magnitude. The magnitude of any vector quantity will always be positive.

Any vector vec(A) can be written as:
vec(A) = A*unit_vec(A)
where A = magnitude of vector vec(A)
and, unit_vec(A) = unit vector along vector vec(A).

Now, E = -dV/ds represents a vector quantity, containing the information of magnitude and direction. So, if the direction is opposite to our ...

Solution provided by:
###### Education
• MSc , Pune University, India
• PhD (IP), Pune University, India
###### Recent Feedback
• " In question 2, you incorrectly add in the \$3.00 dividend that was just paid to determine the value of the stock price using the dividend discount model. In question 4 response, it should have also been recognized that dividend discount models are not useful if any of the parameters used in the model are inaccurate. "
• "feedback: fail to recognize the operating cash flow will not begin until the end of year 3."
• "Great thanks"
• "Perfect solution..thank you"

##### Intro to the Physics Waves

Some short-answer questions involving the basic vocabulary of string, sound, and water waves.

##### Classical Mechanics

This quiz is designed to test and improve your knowledge on Classical Mechanics.

##### Variables in Science Experiments

How well do you understand variables? Test your knowledge of independent (manipulated), dependent (responding), and controlled variables with this 10 question quiz.