Answer:2k
Explanation:
Given
Let K' be the new spring constant of each half
K is the original spring constant
If the original spring is formed using half piece with x_1 and x_2 extension in each spring when same force is applied as for the original spring
then
F=kx
for new spring
x=x_1+x_2
[tex]\frac{F}{k}=\frac{F}{k'}+\frac{F}{k'}[/tex] [from hooke's law]
[tex]\frac{1}{k}=\frac{1}{k'} +\frac{1}{k'}[/tex]
k'=2k