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3 years ago

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The fundamental rule for the attraction and repulsion of magnets is magnetic forces follow the inverse-square law. opposite char

ges attract each other and like charges repel. like poles repel each other; opposite poles attract. magnetic poles attract other magnetic poles.

1 answer:

Hitman42 [59]3 years ago

7 0

Answer:

Explanation:

It is true: the fundamental rule for the attraction and repulsion of magnets is magnetic forces follow the inverse-square law.

The force is given by

$F\alpha \frac{1}{r^{2}}$

It is true: opposite charges attract each other and like charges repel.

It is true: like poles repel each other; opposite poles attract.

It is not true: magnetic poles attract other magnetic poles.

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A large box slides across a frictionless surface with a velocity of 12 m/s and a mass of 4

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p=(4)(12)= 48
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What is a type of matter made up of a combination of elements

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An object is made of glass and has the shape of a cube 0.13 m on a side, according to an observer at rest relative to it. Howeve

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Answer:

$v=0.9833\ c$

Explanation:

The density changes means that the length in the direction of the motion is changed.

Therefore,

$\text{Density} = \frac{m}{lwh}$

Given :

Side, b = h = 0.13 m

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So,

$8100=\frac{3.3}{l \times 0.13 \times 0.13}$

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$0.024= 0.13 \sqrt{1-\frac{v^2}{c^2}}$

$0.184= \sqrt{1-\frac{v^2}{c^2}}$

$0.033= 1-\frac{v^2}{c^2}}$

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3 years ago

Concrete colums are constructed with reinforcing steel in them to make them stronger and more ductile. The reinforcing bars are

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Answer:

$21678.47223\ lbf-in^2$

$383.1109\ lbf-in^2$

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d = Diameter of column = 0.5 inch

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$\dfrac{F_sL}{A_sE_s}=\dfrac{F_cL}{A_cE_c}\\\Rightarrow F_c=\dfrac{F_sA_cE_c}{A_sE_s}\\\Rightarrow F_c=\dfrac{F_s \times 119.4\times 4.1\times 10^6}{8\times \dfrac{\pi \dfrac{1}{2^2}}{4}\times 29\times 10^6}\\\Rightarrow F_c=10.74658F_s$

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$F_c=10.74658F_s\\\Rightarrow F_c=10.74658\times 4256.55807\\\Rightarrow F_c=45743.44182\ lbf$

Stress is given by

$\sigma_s=\dfrac{4256.55807}{\pi \dfrac{1}{2^2}}{4}\\\Rightarrow \sigma_s=21678.47223\ lbf-in^2$

The stress in the steel is $21678.47223\ lbf-in^2$

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The stress in the steel is $383.1109\ lbf-in^2$

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