Answer: 0.516 ft/s
Explanation:
Given
Length of ladder L=20 ft
The speed at which the ladder moving away is v=2 ft/s
after 1 sec, the ladder is 5 ft away from the wall
So, the other end of the ladder is at

Also, at any instant t

differentiate w.r.t.

b) between poles M1 and M2
Explanation:
From the expression, we can deduce that r is the distance between two magnetic poles M1 and M2.
The law of attraction between two magnetic poles states that:
<em> the force of attraction or repulsion between two magnetic poles is a function of the product of the strength of the magnetic poles and the square of the distance between the pole</em>s
Mathematically:
FM = K 
here r is the distance between the poles
FM is the magnetic force between the poles
M1 is the strength of the first magnetic pole
M2 is the strength of the second pole
K is the magnetic field constant
learn more:
magnetic pole brainly.com/question/2191993
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Elemental hydrogen (H, element 1), nitrogen (N, element 7), oxygen (O, element 8), fluorine (F, element 9), and chlorine (Cl, element 17) are all gases at room temperature, and are found as diatomic molecules.
Titanium, Lead, Potassium, and Silicon are solids at normal temperature.
Mercury and bromine (Br) are the only liquid elements at standard pressure and temperature (Hg).
<h3>What are chemical elements?</h3>
A chemical element is a species of atoms, including the pure substance made entirely of that species, that have a specific number of protons in their nuclei. Chemical elements, in contrast to chemical compounds, cannot be reduced by any chemical process into simpler molecules.
To learn more about chemical elements visit:
brainly.com/question/20573603
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Answer:
What is sludge dumping? Sludge is the solid waste in raw sewage. Sludge dumping is discharging that waste into the ocean.
Explanation: