Question

please explain me how to do this

Answer 1

how to do what?

Answer 2

in a radioactive decay of U 238,92 an \[\alpha\]-particle is emitted,and a daughter nuclide Th 234,90 formed.At the constant the \[\alpha\] particle is 1.0*10^-15m from the Th 238,90,find the force on the \[\alpha\] particle

Answer 3

not my field sorry :(

Answer 4

its electrostatic

Answer 5

So from the question you have the following reaction\[U _{92}^{238}\rightarrow He _{2}^{4}+Th _{90}^{234} \] Now the first trick is to recognise that the above reaction began with a neutral uranium atom. That is, the uranium atom contained 92 negative electrons and 92 positive protons.

The second thing to know is that an alpha particle is just the nucleus of the helium atom. That is, it's a helium atom without the 2 electrons, so it has a net charge of \[q_{He} = +2e \] Once you know that (this is partly what the question is testing your knowledge about) then you must come to the conclusion that all of the electrons that were bounded to the uranium nucleus (92 of them) are now bounded to Thorium. Since from the above reaction equation we know that thorium has only 90 protons because the other two went into forming the alpha particle. So that means thorium has a net charge of \[q_{He} = -2e \] Armed with this information we are ready to insert these values and the distance (d) separating the positively charged alpha particle from the negatively charged thorium ion into the Coulomb force (F) equation defined as,\[F=(q_{He}q_{Th})/(4\pi \epsilon_{o}d^{2})\] giving you the answer you require.

Answer 6

thanks