Answer:
a) 0.040625 m
b) 5.02272 J
Explanation:
k = Spring constant
x = Stretched length
F = Force
a)
[tex]F=kx\\\Rightarrow k=\frac{F}{x}\\\Rightarrow k=\frac{4\times 9.81}{0.025}\\\Rightarrow k=1569.6\ N/m[/tex]
[tex]F=kx\\\Rightarrow x=\frac{F}{k}\\\Rightarrow x=\frac{6.5\times 9.81}{1569.6}\\\Rightarrow x=0.040625\ m[/tex]
Extension of the spring would be 0.040625 m
b) Work done in a spring
[tex]W=\frac{1}{2}kx^2\\\Rightarrow W=\frac{1}{2}\times 1569.6\times 0.08^2\\\Rightarrow W=5.02272\ J[/tex]
The work done by the shopper to stretch this spring a total distance of 8.00 cm is 5.02272 J