Imma guess A! Idk if it’s 100% correct tho so I’d check that!
In an alpha decay, an atom emits an alpha particle. An alpha particle consists of 2 protons and 2 neutrons: this means that during this kind of decay, the original atom loses 2 protons and 2 neutrons from its nucleus.
This also means that the atomic number Z of the element (the atomic number is the number of protons in the nucleus) decreases by 2 units in the process, while the mass number A (the mass number is the sum of the number of protons and neutrons) decreases by 4 units.
B. my town is powered by electricity that is generated by the energy from the flow of water through a large dam.
The water from the large dam is example of renewable energy. It can be replenished through rainfall cycle, so it is a renewable form of energy.
1) First of all, we need to find the distance between the two charges. Their distance on the xy plane is
substituting the coordinates of the two charges, we get
2) Then, we can calculate the electrostatic force between the two charges
and
, which is given by
where
is the Coulomb's constant.
Substituting numbers, we get
and the negative sign means the force between the two charges is attractive, because the two charges have opposite sign.
The words "... as shown ..." tell us that there's a picture that goes along
with this question, and you decided not to share it. That's sad and
disappointing, but I think the question can be answered without seeing
the picture.
The net force on the crate is zero. Evidence for this is that fact that
the crate is just sitting there. If the net force on an object is not zero,
then the object is accelerating ... it's either speeding up, slowing down,
or its the direction of its motion is changing. If none of these things is
happening, then the net force on the object must be zero.
