(a)
Law of conservation of momentum:
m1v1+m2v2=(m1+m2)v
since m2=0.1m1
m1v1+0.1m1v2=(1.1m1)v
solve for v
v=(m1)(v1+0.1v2)/(1.1m1)
=(v1+0.1v2)/1.1
(b)
Assuming no loss in total energy,
and assuming v1>v2, then
the shark itself (without food) has lost energy, since its velocity has reduced.
If the food becomes part of the shark, then the shark has gained kinetic energy, since total energy has not changed.
A great white shark of mass m1, coasting through the water in a nearly frictionless way at speed v1 engulfs a tuna of mass m2=0.10 m1 traveling in the same direction at speed v2 swallowing it in one bite.
a) What is the speed of the shark after its meal?
b) Did the shark gain (kinetic) energy, lose energy, or have its energy remain the same in the process?
1 answer