Question

A closely coiled helical spring has a stiffness of 8N/mm. If it extends by 5 mm, the energy absorbed is

• A. 0
• B. 50 N mm
• C. 100 N mm
• D. 10 N mm

Hint:

Spring energy calculations often use \( E = \frac{1}{2} k x^2 \), highlighting the direct relationship between spring stiffness, displacement, and energy storage.

Answer 1

The Correct Option is B

The energy \(E\) absorbed by a spring when it is extended is calculated using the formula \(E = \frac{1}{2} k x^2\), where \(k\) is the stiffness and \(x\) is the extension. For a stiffness of 8 N/mm and an extension of 5 mm: \[ E = \frac{1}{2} \times 8 \times (5)^2 = 100 \times \frac{1}{2} = 50 \text{ N mm} \]