(a) The momentum of a moving object is given by:
[tex] p=mv [/tex]
where m is the mass of the object and v is its speed. In this problem, the mass of the elephant is [tex] m=2000 kg [/tex] and its speed is [tex] v=7.50 m/s [/tex], therefore its momentum is
[tex] p=(2000 kg)(7.50 m/s)=15000 kg m/s [/tex]
(b) We can use the same formula to calculate the momentum of the tranquilizer dart, whose mass is [tex] m=0.04 kg [/tex] and whose speed is [tex] v=600 m/s [/tex]:
[tex] p=mv=(0.04 kg)(600 m/s)=24 kg m/s [/tex]
we see that the elephant's momentum is much larger than the momentum of the dart.
(c) Again, using the same formula, the mass of the hunter is [tex] m=90 kg [/tex], his speed is [tex] v=7.40 m/s [/tex], therefore his momentum is
[tex] p=mv=(90 kg)(7.40 m/s)=666 kg m/s [/tex]
