"b. The nucleus is made of
protons and neutrons and has a positive charge" is the only option that is true about the atomic nucleus. The protons give it a positive charge.
Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. It can either be kinetics or potential. In this problem you know it starting position so you can calculate it's potential energy (PE):
<span>PE=mass∗gravity∗height=0.3kg∗9.8m/s2∗1.8m=?
</span>The answer will typically be given in joules:
1J=kg∗m2s2 Could be wrong... But I believe it is 5.3...? as a final product.
Frequency = 1/time period = 1/0.05 = 20s^-1.
The De Broglie wavelength of the electron is

And we can use De Broglie's relationship to find its momentum:

Given

, with m being the electron mass and v its velocity, we can find the electron's velocity:

This velocity is quite small compared to the speed of light, so the electron is non-relativistic and we can find its kinetic energy by using the non-relativistic formula:
Answer:
A dependent variable is a variable that is tested in an experiment. An independent variable is that can be modified. Depending on what you are testing, the dependent variable will change accordingly to the dependent variable.
- I'm reading this back and it doesn't make much sense, if you want me to reword this I can