An object with a mass of #4 kg# is hanging from a spring with a constant of #2 (kg)/s^2#. If the spring is stretched by # 12 m#, what is the net force on the object?

1 Answer
Jan 10, 2018

24 N upwards


On stretching the spring by 12 meters an added amount of #12*2# N i.e 24 N force is applied on it.
So just after releasing the system the spring tries to reach its original position due to the extra amount of energy added by stretching.
So the object will also move upward due this pull and it's apparent weight will increase by this amount i.e total force acting on the body will be 24 N upwards and it's weight will be(24+40)N or 64 N