Question

A mass of $0.5\, kg$ moving with a speed of $1.5\, m/ s$ on a horizontal smooth surface, collides with a nearly weightless spring of force constant $k = 50\, N/m$. The maximum compression of the spring would be

• A. $0.5\,m$
• B. $0.15\,m$
• C. $0.12\,m$
• D. $1.5\,m$

Answer 1

Answer: (B)

$0.15\,m$

Answer 2

Apply law of conservation of energy, $\frac{1}{2}mv^{2}=\frac{1}{2} kx^{2}$
$\Rightarrow mv^{2}=kx^{2}$ or $0.5\times\left(1.5\right)^{2}=50\times x^{2}$
$\therefore x=0.15\,m$