Answer:
4E
Step-by-step explanation:
The elastic potential energy of an elastic material (e.g a spring, a wire), is the energy stored when the material is stretched or compressed. It is given by
U =
--------------------(i)
Where;
U = potential energy stored
k = spring constant of the material
x = elongation (extension or compression of the material).
From the first statement;
when elongation (x) is 4cm, energy stored (U) is E
Substitute these values into equation (i) as follows;
E =
E = 8k
Make k subject of the formula
k =
[measured in J/cm]
From the second statement;
It is stretched by 4cm.
This means that total elongation will be 4cm + 4cm = 8cm.
The potential energy stored will be found by substituting the value of x = 8cm and k =
into equation (i) as follows;
U =
U =
U =
Therefore, the potential energy stored will now be 4 times the original one.