Velocity of 1 kg block just before it collides with 3 kg block =√2gh=√2000m∕s Using principle of conservation of linear momentum just before and just after collision, we get 1×√2000=4v⇒v=
√2000
4
m/s Initial compression of spring 1.25×106x0=30⇒x0≈0 using work energy theorem, Wg+Wsp=ΔKE ⇒40×x+