Pulley and spring are massless and the friction is absent everwhere. $5\, kg$ block is released from rest. The speed of $5\, kg$ block when $2\, kg$ block leaves the contact with ground is (take force constant of the spring $K = 40\, N/m$ and $g = 10\, m/s^2)$
$\sqrt 2\,m/s$
$2 \sqrt 2\,m/ s$
$2\, m/s$
$4 \sqrt 2\,m/ s$
A spring of spring constant $ 5 \times 10^3$ $ 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 .............. $\mathrm{N-m}$
Write the dimensional formula of $\frac {k}{m}$.
A ball of mass $100 \,g$ is dropped from a height $h =$ $10\, cm$ on a platform fixed at the top of vertical spring (as shown in figure). The ball stays on the platform and the platform is depressed by a distance $\frac{ h }{2}$. The spring constant is.......... $Nm^{-1}$ . (Use $g=10\, ms ^{-2}$ )
Mention the work done by spring force in cylic process.
To simulate car accidents, auto manufacturers study the collisions of moving cars with mounted springs of different spring constants. Consider a typical simulation with a car of mass $1000\; kg$ moving with a speed $18.0\; km / h$ on a smooth road and colliding with a horizontally mounted spring of spring constant $6.25 \times 10^{3} \;N m ^{-1} .$ What is the maximum compression of the spring in $m$?