Electric Fields

4.1.4 Electric Fields

​Electric Field Maps

​•Electric fields…

•exist near CHARGED OBJECTS

•mapped using a POSITIVE test charge

•1 – place test charge

•2 – draw arrow in direction pushed

•3 – this is the field direction

Draw

Draw the electric field lines around the charges

Draw

Draw the electric field around the two charges

​Electric Field Strength

​•Field strength…

• Gets WEAKER with distance

• FORCE exerted per unit CHARGE

Multiple Choice

•An object with a charge of -2 coulombs positioned in a uniform electric field experiences a force of -300 newtons.  What is the strength of the electric field?

• 0.0067 C/N

• 0.0067 N/C

• 150 N/C

• 150 C/N

Multiple Choice

•What is the force experienced by a 0.05 coulomb charge when it is placed in an electric field with a strength of 3E3 newtons per coulomb?

• 0.017 N

• 0.15 N

• 150 N

• 60,000 N

​Parallel Plates

​•Field strength…

•Between plates

•E à Fe = SAME AT ALL POINTS

•Outside plates = ZERO

Draw

Hollow Charged Spheres. Follow the following instructions and your knowledge of electric fields to draw the field outside and inside the sphere. Normal field pattern outside, zero field inside

Multiple Choice

A bean of electrons passes through an electric field where the magnitude of the electric field strength is 3.00E3 N/C. What is the magnitude of the electrostatic force exerted by the electric field on each electron in the beam?

• 5.33E-23 N

• 4.80E-16 N

• 3.00E3 N

• 1.88E22 N

Multiple Choice

Which diagram represents the electric field between two oppositely charged conductive spheres?

• 1

• 2

• 3

• 4

Multiple Choice

An electric field exerts an electrostatic force of magnitude 1.5E-14 N on an electron within the field. What is the magnitude of the electric field strength at the location of the electron?

• 2.4E-33 N/C

• 1.1E-5 N/C

• 9.4E4 N/C

• 1.6E16 N/C