Salt and pepper

This task is about investigating static electricity.
Instructions
  1. Sprinkle salt and pepper into the saucer and mix together well.
  2. Rub the pen quickly back and forth on the felt or wool.
  3. Hold the pen just above the saucer and move it slowly across the salt and pepper mixture.
  4. Change the speed and height of the pen until you can lift the pepper but leave the salt behind.

Question 1Change answer

a)  Why does the pepper "jump" from the saucer?

Question 1Change answer

b)  Why does the pepper "jump" more easily than the salt?