Q.

A spring stretches by 2 mm when it is loaded with a mass of 200 g. From equilibrium position the mass is further pulled down by 2 mm and released. The frequency associated with the system and maximum energy in the spring are ______ Hz and ______ J, respectively. (Take g = 10 m/s2)                [2026]

1 550π and 8×10-3  
2 550π and 8  
3 1050 and 2×10-3  
4 550π and 16×10-3  

Ans.

(1)

K(2×10-3)=(200×10-3)(10)⇒K=1000

(Uspring)max=12×1000×[4×10-3]2=8×10-3 J

T=2πmk=2π200×10-3103

⇒f=12π1042=102π50=550π per sec