Elastic Collision between a neutron and helium nucleus.

[nocho8]

Homework Statement

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to rebound at an angle θ'2 = 41° from the neutron's initial direction. The neutron's initial speed is 6.2 x10^5 m/s. Determine the angle at which the neutron rebounds, θ'1, measured from its initial direction.
__°
What is the speed of the neutron after the collision?
_____m/s
What is the speed of the helium nucleus after the collision?
_____m/s

Homework Equations

conservation of momentum
conservation of energy

The Attempt at a Solution

Wound up with a very messy system of equations involving conservation of momentum in both the x and y directions as well as conservation of energy. Any help would be greatly appreciated!

 

[kuruman]

Can you show some details of what you did? Then perhaps someone will be able to find if you did go wrong and where.