Chapter 21 Electric Charge and Electric Field Interaction
- Slides: 70
Chapter 21 Electric Charge and Electric Field
Interaction of Electric Charge
Charging an object • A glass rod is rubbed with • • • silk Electrons are transferred from the glass to the silk Each electron adds a negative charge to the silk An equal positive charge is left on the rod
Charge + Unit: C, Coulomb −
Electric Charge Electric charge is one of the fundamental attributes of the particles of which matter is made.
Electric Field Like charges (++) Electric dipole: Opposite charges (+−)
Vectors are arrows
What are these vectors?
Magnitude of a vector = Length of the arrow 3 4
What are the magnitudes?
Magnitudes (solution)
Adding and subtracting vectors
Add and subtract
Solution
Notations
Vector Components 4 5 -3
Terminology
Decomposing a vector Hint: Once you know one side of a rightangle triangle and one other angle, you can find all the lengths using cos, sin or tan.
A quick reminder
Trigonometry
Solution
Check
Angles of a vector Find the angles the four vectors make with the positive x-axis. y 30° x
Calculating the angles
Write down the following three vectors in i j notation. Find the sum of these vectors also. 10 o 4. 5 5 4 50 o 60 o
(-1) times a vector? 5 3 4
4 5 3 3 5 4
In General
Adding Vectors Diagrammatically You are allowed to move an arrow around as long as you do not change its direction and length. Method for adding vectors: 1. Move the arrows until the tail of one arrow is at the tip of the other arrow. 2. Trace out the resultant arrow.
Addition of vectors You are allowed to move an arrow around as long as you do not change its direction.
Adding in a different order
Order does not matter
Subtracting Vectors Diagrammatically
Example
Example
Adding vectors 1 Add the three vectors to find the total displacement.
Adding Vectors 2
Electric field is a vector The direction of the electric field is given below:
Vector Notation of E field Charges produce electric field. The closer you are to the charge, the stronger is the electric field. Unit: V/m = N/C q
Another Notation
Store k in your calculator Type: “ 8. 99 E 9” then “STO ” then “ALPHA” then “K” then “ENTER” If q=2 C, r=1. 3 m, to find the E field, type: “K*2/1. 32”
Electric Field (Magnitude) The magnitude of the electric field produced by a single point charge q is give by: Don’t forget the absolute value! Magnitude is always positive.
Warnings + − Observer
Direction of E (one charge)
Example
Example (Continued) The electric field vector is given by the red arrow.
The strategy in finding the electric field vector
Find the unit vectors
Warnings
Example - Two Charges See supplementary notes
More about r: θ θ θ
Example Find the E field at point P P q 1 4 cm q 2 3 cm
Solution P q 1 4 cm q 2 3 cm
Example Find the point P such that E = 0. 7 cm q 1 P x q 2 7 -x
Example q 1 q 2 P x 7 -x
The difference between field vectors and field lines Field vectors Field lines
Properties of field lines • Field lines never cross each other • Field lines never terminate in vacuum • Field lines originate from positive charges and terminate at negative charge • Field lines may go off to infinity • The tangent of a field line gives the direction of the E field at that particular point
Dipole Field vectors Field lines
Similar to this You connects the field vectors to find the field lines.
Electric Field and Electric Force Electric field can be used to calculate the electric force F and E are parallel when q is positive. F and E are opposite when q is negative.
Two point charges E 12 q 1 r q 2 E 21
Coulomb’s Law The mutual force due to two point charges has magnitude:
Another Notation
Finding the Electric Force There are two (equivalent) methods of finding the force on a charge (say, q 1).
Finding the force on a charge +1 n. C -1 n. C P
Motion of a charge in an E field
Line of Charge
Solution
Solution (Cont. )
Solution (Cont. )
- Chapter 21 electric charge and electric field
- Chapter 21 electric charge and electric field
- Units for coulombs
- Dc o/d per item charge
- Difference between charge and electric charge
- Electrons flowing
- Magnitude of magnetic force
- Q factor of capacitor
- Magnetic field
- Electric field of a finite line charge
- Electrostatics formula
- Electric field of a finite line charge
- Sheet of charge electric field
- Formula of electric field
- Properties of coulomb's law
- Electric field lines about a point charge extend
- Electric field of line charge
- Force on charge in electric field
- Electric field due to a continuous charge distribution
- Mention the expression
- Electric field and electric potential
- Potential energy of a system of charges
- Potential energy of an electric field
- Chapter 17 section 1 electric charge and force answer key
- Chapter 6 section 1 electric charge worksheet answers
- Symbol q in electricity
- Database field types and field properties
- Field dependent definition
- Right hand rule for electron in magnetic field
- Does magnetic field exerts force on a static charge
- Electric force equation
- Does magnetic field exerts force on a static charge
- Relationship between v and e
- Emf and electric field
- Electric potential to work
- Copper conductivity
- Gauss law symbol
- What is electric charge measured in
- Section 1 electric charge crossword puzzle answers
- Section 1 electric charge crossword puzzle answers
- Example of charge by contact
- Potential energy between two charges
- What is amber in electricity
- Units of electric charge
- Write coulomb's law in vector form
- Section 1 electric charge
- Electricity section 1 electric charge
- Unit of electrical force
- Charging by conduction
- Unit of electric charge
- Continuous flow of electric charges
- Conduction vs induction
- Charging by contact
- Static electricity examples
- Electric charge
- Stationary electric charge
- What is electricity
- Electric charges and electric forces lesson outline
- Individual differences factors
- Field dependent vs field independent
- E field h field
- Electric field representation
- Physics
- Equation for electric field intensity
- Induced electric field
- Induced electric field in a solenoid
- Electric field practice problems
- Chapter 22 electric fields
- Electric field right hand rule
- Nfpa emergency field guide
- Contoh soal momen dipol