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Why are you trying to answer questions about the fundamental forces and particles behind everything in the universe when I am left unable to even explain what happened last night?

It doesn't seem fair.

Anyway, if you put Newton's 3rd Law to the test - if an action happens and everyone cares about it, does that mean the reaction, because it is the opposite, will not be cared about?

Also, despite the awesomeness of Richard Feynman having graced our world, we cannot explain gravity through some quantum mechanism. Quantum gravity that is compatible with general relativity would give us a unified vision of the world, and indeed—as these delusional maniacs believe—a complete and total explanation of everything that has happened, is happening, and will happen in the universe. Physics researchers would lose their jobs and rejoice and celebrate. All would be explained by a single theory of the world after all.

If the above is true, why then—unless they just lack common sense—would they want to find the answer to everything?

can you explain why with beta+ decay , does it result in a positron(anti-electron) and a neutrino being released? , i kind of get the idea that charge is conserved but can you go into detail about the charge , mass , quark formation and spin, can you also say what particles there are and what their anti particles are ...
This would be much appreciated

I'm actually wondering that same thing...



I'm not sure what you mean when you say "care about it." Newton's third law is just a statement that, for example, if you push on a wall then the wall pushes back on you with the same force in the opposite direction.



Why do you call them delusional? We already have a theory that explains everything in the universe with the exception of gravity.



They most certainly would not. Research on General Relativity and Quantum Mechanics is still ongoing, nearly a century after their original formulation. And they would of course be the leading experts in their field, so it would be very easy for them to find jobs in academia.



Science isn't a political system. Even if it were true that researchers would lose their jobs, science is about the pursuit of knowledge.



In β[SUP]+[/SUP] decay, the weak interaction turns a proton into a neutron. It changes the Up-Down-Up quark configuration (proton) into a Up-Down-Down configuration (neutron). Up quarks have spin +½, and down quarks have spin -½. The process of going from a proton to a neutron therefore changes the total nuclear spin from +½ to -½. As we all know, protons have charge +1 while neutrons have charge 0. In order for charge and spin to be conserved, two new particles - the positron and the neutrino - must be created. The charge of the positron is +1, and its spin is +½. The neutrino has charge 0 and spin +½. So everything works out fine and dandy:

Charge:
Before: 1 proton charge = +1
After: 1 neutron charge + 1 positron charge + 1 neutrino charge = 0+1+0 = +1

Spin:
Before: 2 Up spin + 1 Down spin = ½ + ½ - ½ = +½
After: 1 Up spin + 2 Down spin + 1 positron spin + 1 neutrino spin = ½ - ½ - ½ + ½ + ½ = +½


Mass is trickier to deal with because some gets converted into the kinetic energy of the emitted particles, etc. Energy is conserved in the same way as charge and spin.


In β[SUP]-[/SUP] decay, the exact opposite occurs - i.e. a neutron is changed into a proton and an electron (charge -1, spin -½) and anti-neutrino (charge 0, spin -½) are emitted.


**Spin values of particles can be either positive or negative, depending on the interaction taking place.

1. A 5.0 kg bucket of water is raised from a well by a rope. If the upward acceleration of the bucket is 3.0 m/s^2, find the force exerted by the rope on the bucket.


2.A 2000 kg car is slowed bown uniformly from 20.0 m/s to 5.00 m/s in 4.00 s. What average force acted on the car during this time, and how far did the car travel during the deceleration?

My intent with this thread wasn't exactly homework questions. I'll help you out though:

1. You are given the mass of the bucket, m, and its acceleration, a. Just use Newton's second law to find the net force that must be applied to the bucket to cause this acceleration: F=ma. I'm not going to plug the numbers in for you.


2. Well, since the car was slowed uniformly, this means that a constant acceleration - and therefore force - was applied to the car. You also know the initial and final speeds, as well as how long it took for the speed to change. You can therefore use the following equation to solve for a:

Δv = v[SUB]2[/SUB]-v[SUB]1[/SUB] = at

, where v[SUB]2[/SUB] is the final velocity (5 m/s), v[SUB]1[/SUB] is the initial velocity (20 m/s), and t= the total time the car accelerates (4 s). Once you solve that to find a, you can plug it in to F=ma (along with m=2000 kg) to find the force acting on the car.


For how far the car traveled, you can use the following equation:

Δx = v[SUB]1[/SUB]t + ½at[SUP]2[/SUP]

Where Δx is the distance the car travels, v[SUB]1[/SUB] is the initial velocity of 20 m/s, t=4 s, and a is the value you found above (it should be a negative number).

im doing physics so i can kinda help here

1. Force = mass x acceleration
Force = 5 x 3
force = 15N N=Newtons


2. With this question i think you can use a set of equations called "SUVAT" equations

s = distance or displacement(but call it distance)
t = time(in seconds)
u = initial velocity(velocity to start with)
v = final velocity
a = acceleration

v = u + at

5 = 20 + a x 4

so a = -3.75

s = ut + 1/2 at^2

s = 20x4 + 1/2(-3.75) x 4^2

s = 80 - 30

s = 50m

distance travelled i hope is = 50 m

force = mass x acceleration

average force i hope is = 2000 x -3.75 (ignore minus with acceleration) = 7500N

Hope this helped sorry if any of it is wrong

For example, if I were to, say, make the action of committing rape to someone that I intensely cared about (like Sarah Bareilles) would that mean that people would have an uncaring reaction due to my action being so full of care? Since caring is the opposite of [s]logic[/s] uncaring and all.



The pursuit of knowledge doesn't pay the bills.



Does that possibly mean professors are putting the brakes down on physics because they don't want these leading researchers in the field to take away their jobs?

I'm not sure what you're talking about. Care and uncare are not physical quantities. Newton's third law is a statement about forces (measurable quantities). You're misapplying it to non-physical things.



Actually, it does for physicists. Not to mention that the Nobel Prize is usually ~ $1 million.



Nobody is losing their job. I'm not really sure why you're so adamant about this.

People have lost their jobs. I used to be an astrological theologian. Ever since physics took away my column to some sort of mumbo jumbo about gravity I used to be a very successful catechist.