Question

The magnitude of the momentum of a cat is p. What would be the magnitude of the momentum (in terms of p ) of a dog having two times the mass of the cat if it had the same speed as the cat? What would be the magnitude of the momentum (in terms of p ) of a dog having two times the mass of the cat if it had the same kinetic energy as the cat?

Answer 1

1.
p1= m1•v = p
p2 =m2•v =2•m1•v= 2•p1 =2•p.
2.
KE1=m1•v1²/2.
KE2 = m2•v2²/2=2m1•v2²/2
KE1=KE2
m1•v1²/2 =2m1•v2²/2.
v2=v1/√2.
p1=m1•v1,
p2=m2•v2=2•m1•v1/√2 =√2•p1=√2•p.