Fundamental Principles of Electricity Questions
Do these questions using GRASP. Check your answer against the one given.
1. A pith ball is charged by placing 3.429x1018 electrons onto its surface. What is the charge
on the pith ball? (ans: 0.55 C)
2. The "eye of physics" observes 12 C of charge flow past a point on a wire in 2.0 seconds.
What is the current in the wire? (ans: 6.0 A)
3. To make a fluorescent lamp glow, 300 C of charge is exposed to an electric potential
difference of 30 kV. How much electric energy is transferred into light energy? (ans: 9.0 x10
6
J)
4. At a point near a Van der Graff generator, 15 C of charge is found to have 45,000 J of
energy. What does this information tell us? (ans: It tells us that the voltage at the point is 3.0 kV)
5. Silver has a resistivity of 1.5x10-8 ohms•meter. If the silver wire is 1.0 km long and the wire
is circular in cross section with a diameter of 1.2 mm, what is the resistance of the silver
wire? (ans: 13 Ω)