Three masses 700g, 500g, and 400 g are suspended at the end of a spring a shown and are in equilibrium. When the 700 g mass is removed, the system oscillacts with a period of 3 seconds, when the 500 gm mass is also removed, it will oscillate with a period of

Options

A. 1 s
B. 2 s
C. 3 s
D. `sqrt((12)/(5)s)`

Answer

B

Explanation

Whem mass 700g is removed, the left out mass (500+400)g oscillates with a period of 3 sec-
`3=t=2pisqrt(((500+400))/(k))`
when 500 g mass is also removed, the left out mass is 400 g
`t.=2pisqrt((400)/(k))`
`(3)/(t.)=sqrt((900)/(400))=t.=2` sec