Elastic collision between mosquito and Dinosaur

[Freeman25]

Homework Statement

A very small mosquito is flying west at 5 m/s, when a very massive dinosaur is going east at 3 m/s charges right into it. If the collision is elastic what is the speed of the mosquito when it bounces off the dinosaur.

Homework Equations

Ek= 1/2 mv^2
P=mv

The Attempt at a Solution

Elastic collision so momentum and kinetic energy are conserved

p1m1 = p2m2

I'm really not sure how to go about the solution. Most of my attempts have been theoretical. I'm stumped due to lack of specifics on their masses...

 

[gneill]

You can safely assume that the mass of the dinosaur is so much greater than that of the mosquito that its velocity will not be noticeably changed in the collision. So imagine that you are sitting on top of the dinosaur and observing the collision from that frame of reference. How fast is the mosquito approaching? When it bounces elastically (like a ball hitting a massive wall), how fast will it be receding?

 

[ashishsinghal]

This case has to solved assuming mass of dinosaur as infinitely greater than than that of the mosquito . The dinosaur will continue moving with same velocity while mosquito will be affected a lot.(why?) Now, it would be better to solve this in the frame of dinosaur.