# WJEC GCSE Physics 2 Higher Tier Q5(c)(ii) Help

• Tomos

## Homework Statement

Question 5 (c) (ii) from the paper physics 2 higher tier January 2014 by wjec. There is no mark scheme at the moment of the paper and I do not understand the question. The paper is at the bottom of "papers" at http://www.wjec.co.uk/qualifications/qualification-resources.html?pastpaper=true&subject=Physics&level=gcse and the question is " if a barium nucleus is released with the same kinetic energy as a neutron, explain why the size of its velocity would only be one twelfth (1/12) of the velocity of a neutron". Please help!

N/A

## The Attempt at a Solution

Barium has a greater mass than a neutron?

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KE in this case is given by ##\frac{1}{2} mv^2## . You're close when you think about the difference in masses. What is their ratio? How does ##m## relate to ##v##? Think about it.

KE in this case is given by ##\frac{1}{2} mv^2## . You're close when you think about the difference in masses. What is their ratio? How does ##m## relate to ##v##? Think about it.
Okay thanks!

With a greater mass and an equivalent kinetic energy, the velocity of the barium nucleus will be much small considering the mass is so much greater than that of the neutron. Ke=(1/2) mv^2 therefore if you set up a proportion you could calculate the velocity of the neutron compared to the barium.