Answer:
Electrons are teeny tiny magnets. They have a north and a south pole, too, and spin around an axis. This spinning results in a very tiny but extremely significant magnetic field. Every electron has one of two possible orientations for its axis.In most materials, atoms are arranged in such a way that the magnetic orientation of one electron cancels out the orientation of another. Iron and other ferromagnetic substances, though, are different (ferrummeans iron in Latin). Their atomic makeup is such that smaller groups of atoms band together into areas called domains, in which all the electrons have the same magnetic orientation. Below is an applet that shows you how these domains respond to an outside magnetic field.
Explanation:
The answer is 12.5 kg because 250N / 20m/s^2
I hope that helped
An electric circuit is anything in which electric current flows. Typically it refers to things with wiring like the electronics in your phone, but it can be made of anything that conducts electricity.
Say you have a battery, it basically has a bunch of electrons under a potential (think of gas in a tank under pressure), but the only way for the electrons to move is to move through a conductor, which are molecules with loosely held electrons. If you take a copper wire and touch each end to the two terminals you’ve completed an electric circuit because the electrons can now flow. But you can also put things partway through the wire like a lightbulb, which when the electrons run through it generates light.
Complete Question:
The elastic energy stored in your tendons can contribute up to 35 % of your energy needs when running. Sports scientists have studied the change in length of the knee extensor tendon in sprinters and nonathletes. They find (on average) that the sprinters' tendons stretch 43 mm , while nonathletes' stretch only 32 mm . The spring constant for the tendon is the same for both groups,
. What is the difference in maximum stored energy between the sprinters and the nonathlethes?
Answer:

Explanation:
Sprinters' tendons stretch, 
Non athletes' stretch, 
Spring constant for the two groups, k = 31 N/mm = 3100 N/m
Maximum Energy stored in the sprinter, 
Maximum energy stored in the non athletes, 
Difference in maximum stored energy between the sprinters and the non-athlethes:

Answer: Could you please add the answer choices.
Explanation:
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