<span>The force of static friction F equals the coefficient of friction u times the normal force N the object exerts on the surface: F = uN. N is the centripetal force of the wall on the people; N = ma_N, where m is the mass of the people and a_N is the centripetal acceleration.
The people will not slip down if F is greater than the force of gravitation: F = uma_N > mg, or u > g/a_N.
a_N is the velocity v of the people squared divided by the radius of the room r: a_N = v^2/r.
The circumference of the room is 2 pi r = 28.3 m. So v = 28.3 * 0.8 m/sec = 22.6 m/sec.
So a_N = 114 m/sec^2.
g = 9.81 m/sec^2, so u must be at least 9.81/114 = 0.086.</span>
Answer:
(A) She needs to move the decimal point by 3 places
Answer:

Explanation:
One mole of a substance contains the same amount of representative particles. These particles can be atoms, molecules, ions, or formula units. In this case, the particles are atoms of titanium.
Regardless of the particles, there will always be <u>6.02*10²³</u> (also known as Avogadro's Number) particles in one mole of a substance.
Therefore, the best answer for 1 mole of titanium is D. 6.02*10²³ atoms.
Answer:
The mass of the products and reactants are the same on both sides of the equation.
The number of atoms of products and reactants are equal and hence it proves the law of conservation of mass.
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To solve this problem it is necessary to apply the concepts related to the principle of superposition and the equations of destructive and constructive interference.
Constructive interference can be defined as

Where
m= Any integer which represent the number of repetition of spectrum
= Wavelength
d = Distance between the slits.
= Angle between the difraccion paterns and the source of light
Re-arrange to find the distance between the slits we have,



Therefore the number of lines per millimeter would be given as



Therefore the number of the lines from the grating to the center of the diffraction pattern are 380lines per mm