Four lightweight balls A, B, C, and D are suspended by threads. Ball A has been touched by a plastic rod that was rubbed with wool. When the balls are brought close together, without touching, the following observations are made: Balls B, C, and D are attracted to ball A. Balls B and D have no effect on each other. Ball B is attracted to ball C. Match the words in the left column to the appropriate blanks in the sentences on the right. have plastic or glass charge have plastic charge or be neutral have glass charge or be neutral have plastic charge have glass charge are neutral has plastic charge has glass charge is neutral Al three balls are attracted to ball A. so they could Balls B and D have no effect on each other, so balls B and D Ball B is attracted to ball C. so ball C

Four lightweight balls A, B, C, and D are suspended by threads. Ball A has been touched by a plastic rod that was rubbed with wool. When the balls are brought close together, without touching, the following observations are made: Balls B, C, and D are attracted to ball A. Balls B and D have no effect on each other. Ball B is attracted to ball C. Match the words in the left column to the appropriate blanks in the sentences on the right. have plastic or glass charge have plastic charge or be neutral have glass charge or be neutral have plastic charge have glass charge are neutral has plastic charge has glass charge is neutral Al three balls are attracted to ball A. so they could Balls B and D have no effect on each other, so balls B and D Ball B is attracted to ball C. so ball C