Lesson Plan

• Describe the definition of an electric field and how it relates to the force on a test charge.
• Explain how electric field lines represent direction and magnitude of the field.
• Calculate electric field strength for point charges using Coulomb’s law.
• Apply the superposition principle to determine the net electric field from multiple charges.
• Interpret field‑line diagrams to predict the direction of forces on charges.

• Projector or interactive whiteboard
• PowerPoint/Google Slides with field‑line animations
• Printed worksheet with example problems
• PhET “Charges and Fields” simulation (or similar)
• Whiteboard and markers
• Calculator for each student

Begin with a quick static‑electricity demo (rubbed balloon attracting paper) to spark curiosity. Ask students what they think is happening to the paper and link it to an invisible “field”. Review prior knowledge of charge types and Coulomb’s law, then state that today they will be able to describe and calculate electric fields.

1. Do‑Now (5'): Students answer a short question on charge properties on the board.
2. Direct Instruction (10'): Explain the definition of an electric field, introduce field‑line conventions with slides.
3. Guided Practice (12'): Work through the point‑charge field formula together, using the example of two charges from the notes.
4. Simulation Activity (10'): Students explore the PhET simulation in pairs, manipulating charge magnitude and position, recording observations.
5. Independent Worksheet (10'): Solve a new problem requiring calculation of net field using superposition.
6. Check for Understanding (5'): Quick “exit ticket” – one sentence describing how field direction is determined.

Summarise that an electric field is a region where a charge feels a force, visualised by field lines, and that the field strength can be calculated and combined using superposition. Collect the exit tickets and remind students to complete the optional homework worksheet on drawing field‑line diagrams for multiple charges.