Answer:
A
Explanation:
Let's rule out some of the options. C makes no sense because static charges will create electric fields only, so the charge has to move. D makes no sense because monopoles do not exist. We can rule out B because when a charge is moving at a constant velocity. You can use Maxwell's equations and general relativity to figure out that at a constant velocity, you can't produce an electromagnetic wave because there is no magnetic field. Therefore the answer is A. When you have an oscillating or accelerating electric charge, you will produce an EM wave.
The hot immediately increase the temperature of the cold water until they both reach equilibrium state.
Answer: They will NOT connect because like poles are facing each other, and like poles repel each other.
Answer:
the force of the plow pulling backward on the tractor
Explanation:
What a delightful little problem !
Here's how I see it:
When 'C' is touched to 'A', charge flows to 'C' until the two of them are equally charged. So now, 'A' has half of its original charge, and 'C' has the other half.
Then, when 'C' is touched to 'B', charge flows to it until the two of <u>them</u> are equally charged. How much is that ? Well, just before they touch, 'C' has half of an original charge, and 'B' has a full one, so 1/4 of an original charge flows from 'B' to 'C', and then each of them has 3/4 of an original charge.
To review what we have now: 'A' has 1/2 of its original charge, and 'B' has 3/4 of it.
The force between any two charges is:
F = (a constant) x (one charge) x (the other one) / (the distance between them)².
For 'A' and 'B', the distance doesn't change, so we can leave that out of our formula.
The original force between them was 3 = (some constant) x (1 charge) x (1 charge).
The new force between them is F = (the same constant) x (1/2) x (3/4) .
Divide the first equation by the second one, and you have a proportion:
3 / F = 1 / ( 1/2 x 3/4 )
Cross-multiply this proportion:
3 (1/2 x 3/4) = F
F = 3/2 x 3/4 = 9/8 = <em>1.125 newton</em>.
That's my story, and I'm sticking to it.
