A man have to get their friend bond with someone they like a lot closer. Then, if the man is ready to confess his feeling, try buying his love of his life their favorite flower or favorite candy/food.

hope this help-(even though im a girl ;v;)

3 0

3 years ago

The illumination of an object by a light source is directly proportional to the strength of the source and inversely proportiona

ElenaW [278]

Exactly 4(4 - 2*2^(1/3) + 2^(2/3)) feet, or approximately 12.27023581 feet. Let's first create an equation to calculate the relative intensity of the light based upon the distance D from the brighter light source. The distance from the dimmer light source will of course be (20-D). So the equation will be: B = 4/D^2 + 1/(20-D)^2 The minimum and maximum can only occur at those points where the slope of the equation is 0. And you can determine the slope by using the first derivative. So let's calculate the first derivative. B = 4/D^2 + 1/(20-D)^2 B' = d/dD [ 4/D^2 + 1/(20-D)^2 ] B' = 4 * d/dD [ 1/D^2 ] + d/dD [ 1/(20-D)^2 ] B' = 4(-2)D^(-3) + (-2)(20 - D)^(-3) * d/dD [ 20-D ] B' = -8/D^3 - 2( d/dD [ 20 ] - d/dD [ D ] )/(20 - D)^3 B' = -8/D^3 - 2(0 - 1)/(20 - D)^3 B' = 2/(20 - D)^3 - 8/D^3 Now let's find a zero. B' = 2/(20 - D)^3 - 8/D^3 0 = 2/(20 - D)^3 - 8/D^3 0 = 2D^3/(D^3(20 - D)^3) - 8(20 - D)^3/(D^3(20 - D)^3) 0 = (2D^3 - 8(20 - D)^3)/(D^3(20 - D)^3) 0 = 2D^3 - 8(20 - D)^3 8(20 - D)^3 = 2D^3 4(20 - D)^3 = D^3 4(8000 - 1200D + 60D^2 - D^3) = D^3 32000 - 4800D + 240D^2 - 4D^3 = D^3 32000 - 4800D + 240D^2 - 5D^3 = 0 6400 - 960D + 48D^2 - D^3 = 0 -6400 + 960D - 48D^2 + D^3 = 0 D^3 - 48D^2 + 960D - 6400 = 0 We now have a simple cubic equation that we can use the cubic formulas to solve. Q = (3*960 - (-48)^2)/9 = 64 R = (9*(-48)*960 - 27*(-6400) - 2*(-48)^3)/54 = -384 D = Q^3 + R^2 = 64^3 + (-384)^2 = 409600 Since the value D is positive, there are 2 imaginary and 1 real root. We're only interested in the real root. S = cbrt(-384 + sqrt(409600)) S = cbrt(-384 + 640) S = cbrt(256) S = 4cbrt(4) T = cbrt(-384 - sqrt(409600)) T = cbrt(-384 - 640) T = cbrt(-1024) T = -8cbrt(2) The root will be 4cbrt(4) - 8cbrt(2) + 48/3 So simplify 4cbrt(4) - 8cbrt(2) + 48/3 =4cbrt(4) - 8cbrt(2) + 16 =4(cbrt(4) - 2cbrt(2) + 4) = 4(4 - 2*2^(1/3) + 2^(2/3)) Which is approximately 12.27023581 This result surprises me. I would expect the minimum to happen where the intensity of both light sources match which would be at a distance of 2/3 * 20 = 13.3333 from the brighter light source. Let's verify the calculated value. Using the brightness equation at the top we have: B = 4/D^2 + 1/(20-D)^2 Using the calculated value of 12.27023581, we get B = 4/D^2 + 1/(20-D)^2 B = 4/12.27023581^2 + 1/(20-12.27023581)^2 B = 4/12.27023581^2 + 1/7.72976419^2 B = 4/150.5586868 + 1/59.74925443 B = 0.026567713 + 0.016736611 B = 0.043304324 And the intuition value of 13.33333333 B = 4/D^2 + 1/(20-D)^2 B = 4/13.33333333^2 + 1/(20-13.33333333)^2 B = 4/13.33333333^2 + 1/6.666666667^2 B = 4/177.7777778 + 1/44.44444444 B = 0.0225 +0.0225 B = 0.045 And the calculated value is dimmer. So intuition wasn't correct. So the object should be placed 4(4 - 2*2^(1/3) + 2^(2/3)) feet from the stronger light source, or approximately 12.27023581 feet.

5 0

3 years ago

Camphor, a white solid with a pleasant odor, is extracted from the roots, branches, and trunk of the camphor tree. Assume you di

katrin [286]

Answer: The molarity of solution is 0.799 M , molality of solution is 1.02 m, mole fraction of camphor is 0.045 and mass percent of camphor in solution is 13.43 %

Explanation:

Calculating the molarity of solution:

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}$

Given mass of camphor = 70.0 g

Molar mass of camphor = 152.2 g/mol

Volume of solution = 575 mL

Putting values in above equation, we get:

$\text{Molarity of camphor}=\frac{70\times 1000}{152.2\times 575}\\\\\text{Molarity of camphor}=0.799M$

Calculating the molarity of solution:

To calculate the mass of ethanol, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of ethanol = 0.785 g/mL

Volume of ethanol = 575 mL

Putting values in above equation, we get:

$0.785g/mL=\frac{\text{Mass of ethanol}}{575mL}\\\\\text{Mass of ethanol}=(0.785g/mL\times 575mL)=451.38g$

To calculate the molality of solution, we use the equation:

$\text{Molality of solution}=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ (in grams)}}$

where,

$m_{solute}$ = Given mass of solute (camphor) = 70 g

$M_{solute}$ = Molar mass of solute (camphor) = 152.2 g/mol

$W_{solvent}$ = Mass of solvent (ethanol) = 451.38 g

Putting values in above equation, we get:

$\text{Molality of camphor}=\frac{70\times 1000}{152.2\times 451.38}\\\\\text{Molality of camphor}=1.02m$

Calculating the mole fraction of camphor:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For camphor:

Given mass of camphor = 70 g

Molar mass of camphor = 152.2 g/mol

Putting values in equation 1, we get:

$\text{Moles of camphor}=\frac{70g}{152.2g/mol}=0.459mol$

For ethanol:

Given mass of ethanol = 451.38 g

Molar mass of ethanol = 46 g/mol

Putting values in equation 1, we get:

$\text{Moles of ethanol}=\frac{451.38g}{46g/mol}=9.813mol$

Mole fraction of a substance is given by:

$\chi_A=\frac{n_A}{n_A+n_B}$

Moles of camphor = 0.459 moles

Total moles = [0.459 + 9.813] = 10.272 moles

Putting values in above equation, we get:

$\chi_{(camphor)}=\frac{0.459}{10.272}=0.045$ \

Calculating the mass percent of camphor:

To calculate the mass percentage of camphor in solution, we use the equation:

$\text{Mass percent of camphor}=\frac{\text{Mass of camphor}}{\text{Mass of solution}}\times 100$

Mass of camphor = 70 g

Mass of solution = [70 + 451.38] = 521.38 g

Putting values in above equation, we get:

$\text{Mass percent of camphor}=\frac{70g}{521.38g}\times 100=13.43\%$

Hence, the molarity of solution is 0.799 M , molality of solution is 1.02 m, mole fraction of camphor is 0.045 and mass percent of camphor in solution is 13.43 %

3 0

3 years ago

How are atoms connected to Electricity

qwelly [4]

The protons and electrons of an atom are attracted to each other. They both carry an electrical charge. Protons have a positive charge (+) and electrons have a negative charge (-). The positive charge of the protons is equal to the negative charge of the electrons.

5 0

2 years ago