What are large nuclei unstable?

Ben(55 kg) is standing on very slippery ice when junior(25kg) bumps into him. junior was moving at a speed of 8m/s before the collision and ben and junior embrace after the collision. find the speed of ben and junior as they move across the ice after the collision .

Gunpowder residue is most likely to show up where on a shooters hands

In a good thermo flask the main cause of heat loss is