Question

Any physics legends to answer my question ??

Answer 1

Solution is in the attachment

Answer 2

Answer:

We know that,

Energy stored in a spring = kx² / 2

So we are given that,

• k = 400 N m⁻¹
• E = 8 J

We are required to find the elongation which is 'x'

Substituting in the formula we get,

⇒ 8 J = 400 × x² / 2

⇒ 2 × 8 J = 400 x²

⇒ 16 J = 400 x²

⇒ 16 J / 400 = x²

⇒ x² = 0.04

⇒ √x² = √0.04

⇒ x = 0.2 m

Hence the elongation of the spring is 0.2 m

Option ( b ) is correct.