The effective length of the first magnet is two times that of the second magnet. The effective length of the third magnet is one-third of the first magnet. If the effectiv lengthof the second magnet is 7.5 cm, the effective length of the third magnet is ______

The effective length of the first magnet is two times that of the seco

1.	The effective length of the first magnet is two times that of the second magnet. The effective length of the third magnet is one-third of the first magnet. If the effectiv lengthof the second magnet is 7.5 cm, the effective length of the third magnet is ______
Answer» 5 cm 15 cm 2.5 cm 7.5 cm Solution :EFFECTIVE length of second MAGNET =7.5 cm. Therefore, effective length of the first magnet =`2xx7.5` `=15 cm ` Therefore, effective length of the THIRD magnet `=1//3xx15 cm` `= cm. ` Hence , the CORRECT option is (a).