Unit 4 - Electricity & Magnetism

Electrostatics - Sub-Unit 4.1

Sub-Unit 4.1 Note Packet

4.1.1 Elementary Charge

• Objectives
• Convert elementary charge charge in coulombs.
• Determine if a particular charge (in either unit) is permissible.
• Determine the charge on an object given the number of electrons and/or protons present on the object.
• Given charge in coulombs, determine excess/deficiency of electrons.
• Know that charge must be conserved in all interactions between objects.
• Understand the reason for charge flow and the way in which charge will redistribute to minimize stored energy.
• Determine the direction of charge flow in a system.
• Determine the final charge on two or more objects after they interact.
• Understand the charge distribution and flow of charge on an electroscope in response to a charge held near its knob or touching its knob.
• Determine the charge on an electroscope based on the response of its leaves to the presence of a charged object.
• Explain whether a set of leaves will converge or diverge based on actions of charged objects near the knob of an electroscope.

• Activities
• Labs

4.1.2 Transfer of Charge

• Objectives
• Understand the operation of the Law of Conservation of Charge.
• Explain and sketch the processes of polarization, induction, conduction, grounding, and flow of charge
• Understand objects with like charge repel; objects with unlike charge attract.
• Understand that neutral objects are attracted to any object with charge.
• Determine the charge on an object based on descriptions of tests using charged rods or other objects.
• Explain how the charge on an object can be determined using charged rods or other objects.

• Activities
• Labs
• Videos

4.1.3 Coulomb’s Law

• Objectives
• Understand that the electrostatic force between two objects is directly proportional to their charge and inversely proportional to the distance between them.
• Calculate Fe given two charges and distance between them.
• Determine how electrostatic force is changed by changing the amount of charge on one or both objects.
• Determine how electrostatic force is changed by changing the distance between two charged objects.

• Activities
• Labs
• Videos

4.1.4 Electric Fields

• Objectives
• Determine: the strength of an electric field; force on a charge; or amount of charge using the electric field equation.
• Sketch a graph relating electric field strength to distance.
• Select/sketch diagrams of electric fields near: point charges; systems of point charges; and/or a set of parallel charged plates.
• Determine direction in which the electric field near an object points.
• Compare electric field strengths at different points.
• Determine rate of acceleration for charged objects in electric fields.
• Compare rates of acceleration for charged objects with the same or different masses and/or charges placed in electric fields.
• Select/sketch the path of a charged object as it moves through an electric field.

• Activities
• Labs
• Videos

4.1.5 Electric Potential

• Objectives
• Understand that moving a charged object to a higher electrical potential requires working against an electric field while allowing an electric field to do work results in lower electric potential.
• Determine the amount of electrical potential gained when work is done on a charged object against an electric field.
• Determine the amount of energy needed to move a charged object from a lower electrical potential to a higher one.
• Determine the amount of kinetic energy gained when a charged object is moved by an electric field.
• Determine whether electrical potential energy is being gained or lost in a system.
• Convert joules electron-volts.

• Activities
• Labs
• Videos

 Lesson # Title Slideshows Videos Practice Labs 4.1.1 Elementary Charge Slides 4.1.1 Video 4.1.1 WS 4.1.1 4.1.2 Transfer of Charge Slides 4.1.2 Video 4.1.2 WS 4.1.2 4.1.3 Coulomb's Law Slides 4.1.3 Video 4.1.3 WS 4.1.3 4.1.4 Electric FIelds Slides 4.1.4 Video 4.1.4 WS 4.1.4 4.1.5 Electric Potential Slides 4.1.5 Video 4.1.5 WS 4.1.5

Regents Physics: Unit 4 - Electricity & Magnetism