@Jasmine charge conservation just means the the charge of the decay product plus the charge of the alpha particle add up to the charge of the original nucleus.
i.e. the charge of the decay product is 2e less than the charge of the original nucleus, and the He nucleus carries away the missing 2e charge.
@Jasmine yes, though the decay is such a high energy that the electrons around the atom can be displaced. The decay produces a charged object, but how many electrons are left round that charged object will vary in a random way.
Well the protons and neutrons in a nucleus live in orbitals just like the electrons in an atom live in orbitals. Gamma decay happens when a nucleus starts in an excited state, like a hydrogen atom in a 2p state, and a proton or neutron in the nucleus decays to a lower energy orbital.
The photon emitted is the difference in energy between the two nuclear orbitals, and in nuclei the orbital energies are huge so the photon emitted is a gamma ray not visible light.
Nuclear energies are so much higher than the energies of the electrons that in most cases you can just ignore the electrons. e.g. an isolated nucleus would decay in exactly the same way as a nucleus in a neutral atom.
If its given in the question that an atom undergoes beta - decay and subsequently emits gamma rays, how are we going to utilise the information that 'it undergoes gamma decay'
Beta decay is when a neutron in the nucleus decays to a proton and an electron. The electron zooms off leaving just the proton. But this often leaves the nucleus in an excited state i.e. the proton created by the beta decay is in a higher energy orbital than it could be.
So after the initial beta decay it's often the case that the proton then decays into a lower energy orbital and emits a gamma ray photon.
@Jasmine yes, the energy is simply the mass lost times c^2.
In nuclear reactions mass is usually treated as the same as energy. In fact we usually measure particle masses in units of energy. For example any nuclear physicist will tell you that the mass of an electron is 511 keV or the mass of a proton/neutron is around a GeV.
So you just take the total energy before the decay and subtract off the rest mass energy of all the products. Then the difference is the energy released as a photon or KE.
@Jasmine heat is a collective property. A single particle doesn't have a temperature. You can only define a temperature when you have lots of particles in an assembly.
Well you aren't told the masses of the X and Y nuclei, so you can't calculate the energy difference from the mass change. Note that the mass of the nucleus is not the same as the masses of the protons and neutrons inside it.
@pi-π Ah, I suspect that is referring to the voltage measured across the terminals of a battery, or other voltage source. This is the EMF minus the voltage drop across the internal resistance i.e. V = E - IR_i, where R_i is the internal resistance.
A particle of mass 3m is projected from point-A with speed 0 3v as shown in figure. When the particle is at point P, it explodes in three identical particles. :::
we conserve mechanical energy just before and after explosion:False
@JohnRennie we are talking about explosion during projectile motion
So initially the projectile is having some mechanical energy
In general you wouldn't solve questions like this using the work energy theorem because it's impossible to know how much of the chemical energy got converted to mechanical energy.
Typically you use conservation of momentum.
Have you got an example question we could look at?
D is less obvious, but if we assume the explosion happens very quickly the impulse delivered by the gravitational force will be small because $t$ is small.
An explosion falls into that category because the actual explosion only lasts a very short time. The explosion delivers a large total impulse only because the forces are enormous!