What element has an r. m.m of 72

Germanium

Explanation:

The element Germanium is one with a relative molecular mass of 72. This corresponds to the mass number of this element.

Relative molecular mass of an element is the mass of a formula unit to that of a carbon-12 atom.

The chemical symbol of Germanium is Ge. It is a lustrous and hard metalloid belonging to the carbon group.

It was discovered by Clemens Alexander Winkler.

ok whats the question if not i cannot you i need question and need a thing to answer

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied