Question

A spring of spring constant 5 × 10³ N/m is stretched initially by 5 cm from the unstretched position. Then the work required to stretch it further by another 5 cm is:

Options

• 18.75 J

• 25.00 J

• 6.25 J

• 12.50 J

Answer 1

18.75 J

Explanation:

W₁ = `1/2 xx 5 xx 10^3 (0.05)^2`

W2  = `1/2 xx 5 xx 10^3 (0.10)^2`

∴ ΔW = `1/2 xx 5 xx 10^3 xx 0.15 xx 0.05`

= 18.75 J