Five balss numbered 1,2,3,4,and 5 are suspended using separated threads. The balls (1,2),(2,4) and (4,1) show electrostatic attraction while balls (2,3) and (4,5) show repulsion. Therefore, ball 1 must be

Options

A. negatively charged
B. Positively charges
C. neutral
D. made of metal

Answer

C

Explanation

`{:(1,2,3,4,5),(+,-,,+,):}`
If 1 is positively charged, then 2 should be negatively charged, then 4 should be positively charged. Now 1 and 4 cannot attract. It means ball 1 should be neutral (2 and 4 cannot be neutral because they are showing repulstion with 3 and 5, respectively).