E, there is no state of matter that has no particle motion, however a solid's particles are only vibrating.
Answer:
The formula comes from Lorentz force law which includes both the electric and magnetic field. If the electric field is zero, the force law for just the magnetic field is <u>F=q(ν×B</u>) . Here, F is force and is a vector because the force acts in a direction. q is the charge of the particle. v is velocity and is a vector because the particle is moving in some direction. B is the magnetic flux density.
We can derive an expression for the magnetic force on a current by taking a sum of the magnetic forces on individual charges. (The forces add because they are in the same direction.) The force on an individual charge moving at the drift velocity vd. Since the magnitude of B is constant at every line element of the loop (circle) and it dot product with the line element is B dl everywhere, therefore
∮B dl=μ0 I
B ∮dl=μ0 I
B 2πr=μ0 I
B=μ02πr Id=μ0/4π I dl×rr3
Since, r can be written as r=(rcosθ,rsinθ,z) and dl as dl=(dl,0,0) And now, if we take the cross product we would get
dl×r=−z dlj^+rsinθk^
and therefore the magnitude of dB is equal to
dB=μ0/4π I |dl×r|/r3=μ0/4π I z2+r2sin2θ−−−−−−−−−−√dl/r3
Thus, magnetic field is depending on r,θ,z.
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The force that prevents motion when the surfaces of two objects come into contact is known as friction. Friction decreases a machine's mechanical advantage, or, to put it another way, reduces the output to input ratio.
<h3>How can I figure out the frictional force?</h3>
The resistive force of friction (Fr) divided by the normal or perpendicular force (N) pushing the objects together yields the coefficient of friction (fr), which is a numerical value.
The formula fr = Fr/N serves as a representation of it.
Therefore, 100N of force is needed to move an item with a mass of 50 kg.
It will accelerate by 10 m/s2.
If a substance's mass does not change over time, friction cannot affect it. Instead, friction can be affected in a variety of ways by an object's mass.
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Answer: an ectomorph is a body type that struggles to gain weight and muscle
