I'm doing what's called "test repair" for my class where we correct the answers we got wrong on the test. In order to get points back, however, we have to explain WHY that answer is the correct one. Can someone help me with these?

Question

39. Nuclear forces exist because the particles in the nucleus are:
b) close together

50. The deflection of cathode rays in Thomson's experiments was evidence of the ________ nature of electrons:
a) wave
b) charged
c) particle

I'm pretty sure the last one is c) particle [I originally put d) spinning, but it was wrong], but I'm not exactly sure how to explain it, and the other one as well. Any help is GREATLY appreciated!!

Answer 1

I'm not sure what the right answers are from your work. I assume that for the first one, b is the choice you SHOULD have chosen. If that is the case, then the explanation is that there are so many particles in such a small space that nuclear forces are necessary to keep the nucleus from breaking apart. After all, the protons have a positive charge and we know like charges repel so something must be there to keep the protons from flying everywhere. I hope this is what you need.
For #2. The deflection was proof of the charged nature of the electron. (You could make a case for particle being correct, too, because most of the literature makes a point that J. J. Thomson's experiment proved that electrons were particles; however, the word deflection makes me go with charged.) The electrons in the glass tube passed between charged plates on the outside of the glass tube. The electrons (particles) were deflected towards the + plate and away from the - plate, showing that they were negatively charged. In fact, Thomson went on to measure the charge to mass tatio (e/m).

Answer 2

Yes, the answer you gave me for the first one was exactly what I needed -- sorry I didn't make it clear enough as to what I needed :( lol.

I totally understand both explanations! Thanks!! :D