1. If I bring a charged rod to a leaf electrometer: A] nothing will happen B] nothing will happen until I touch the electrometer with the rod - then the leaves will spread apart C] the leaves will spread apart when I get the rod close to the electrometer

2. What is the direction of the electric force on a negative charge at 1? Ans:left A] to the right B] to the left C] up D] down What is the direction of the electric force on a positive charge at 2?Ans: left

3. If I put a + charge at 3., what is the direction of the electric force? Ans: C A] straight down, directly toward the - charge B] straight up, directly away from the - charge C] a little to the right from straight down D] a little to the left from straight down

4. What could be the charges here? Assume that all field lines are shown. Ans: B A] Q 1 = +3C, Q 2 = -2 C B] Q 1 = +18C, Q 2 = -10 C C] Q 1 = -18C, Q 2 =+10 C D] Q 1 = +9 C, Q 2 = +5 C E] none of these