Answer:k=4593.75
Explanation:
Given
length of spring =20 cm
maximum compression in spring is x=8 cm
mass of mug m=300 gm
maximum height to which cup is needed to raise is h=5 m
By conserving Energy i.e. Elastic Potential Energy will be converted in to Potential energy of cup
[tex]\frac{kx^2}{2}=mgh[/tex]
where [tex]k=spring\ constant[/tex]
[tex]\frac{k\cdot (0.08)^2}{2}=0.3\times 9.8\times 5[/tex]
[tex]k=\frac{0.3\times 9.8\times 5\times 2}{64\times 10^{-4}}[/tex]
[tex]k=4593.75 N/m[/tex]
so we should use a spring with spring constant k=4593.75 N/m
