Exam (elaborations) Lab 2: Electric Field and Potential objectives (PHYS1102)

Exam (elaborations) Lab 2: Electric Field and Potential objectives (PHYS1102) Pre-Lab Questions 1. How are electric potential and electric field similar? How are they different? Each of them exists in the presence of a charge. Also, they both are related by E=-grad*V. Electric potential is scalar and electric field is a vector. 2. Draw the equipotential lines for a single, positive, charge. 3. If you were to walk on an equipotential line, how would your electric potential change over time? It wouldn’t change because it’s the same at all points. 4. What does it mean when equipotential lines are closer together? What does it mean when they are farther apart? Close together means its strong, farther apart means it’s a weak electric field. 5. What direction do electric fields travel? It is perpendicular to the equipotential line from high to low potential. 6. How can you tell whether an electric field is strong or weak by observing an electric field map? The more field lines means its stronger, less field lines means its weaker at that location. 7. What would the electric field lines look like if the electric field was constant? They would be parallel and uniform. 8. Can there be a point in space where there is an electric field but no electric potential? Explain you answer. It is possible if the two charges of the same magnitude are separated the midpoint joining their electric fields would cancel and be zero. 9. Use Figure 5 to answer the following questions: Figure 5: Charged particles P (left) and Q (right). a. Are charges P and Q negative or positive? How do you know? They are positive since the electric charge is going away from them.