- #1

- 3

- 0

## Homework Statement

A neutron (mass 1.7x10

^{-27}kg) traveling at 2.7 km/s hits a stationary lithium nucleus (mass 1.2x10

^{-26}kg). Afterwards, the velocity of the lithium nucleus is 0.40 km/s at 54° to the original direction of the motion of the neutron. If the speed of the neutron after the collision is 2.5 km/s, in what direction is it traveling?

[Answer: 66° from initial direction of neutron's velocity]

## Homework Equations

Givens:

m

_{1}= 1.7x10

^{-27}kg

v

_{1x}= 2.7 km/s

v'

_{1x}= (2.5)cosθ

v'

_{1y}= -(2.5)sinθ

m

_{2}= 1.2x10

^{-26}kg

v

_{2x}= 0 km/s

v'

_{2x}= (0.4)cos54°

v'

_{2y}= (0.4)sin54°

Equations:

m

_{1}v

_{1x}= m

_{1}v'

_{1x}+m

_{2}v'

_{2x}

0= m

_{1}v'

_{1y}+ m

_{2}v'

_{2y}

## The Attempt at a Solution

I plugged in my values into the two equations, and for the first equation using the x-values I got θ= 65.42° and the second using the y-values I got 65.51°. I was wondering if anyone could point me in the right direction?

I've attached a diagram of my thought process.