Answer:
9 cm.
Explanation:
The energy used for stretch the spring from to
will be ,
The energy used for stretch the spring from to
will be ,
using the energy of spring formula ,we find that
Dividing both the equation will get,
Therefore, the natural length of the spring is, 9 cm.
Answer
given,
Tension of string is F
velocity is increased and the radius is not changed.
the string makes two complete revolutions every second
consider the centrifugal force acting on the stone
=
now centrifugal force is balanced by tension
T =
From the above expression we can clearly see that tension is directly proportional to velocity and inversely proportional to radius.
When radius is not changing velocity is increasing means tension will also increase in the string.