Answer:
Speed of the mass is 2.2 m/s
Explanation:
It is given that,
Mass of the object, m = 1.5 kg
Spring constant of the spring, k = 120 N/m
The spring is compressed by a distance of, x = 0.25 m
The mass is released from this compressed position, then the initial kinetic energy of block is equal to the spring potential energy i.e.
v is the speed of the mass.
v = 2.23 m/s
The speed of the mass as it passes the natural length of the spring is 2.2 m/s. Hence, the correct option is (d).