Saturday

July 30, 2016
Total # Posts: 2,317

**Chemistry**

lamda * f = c where c is the speed of light = 3*10^8 m/s; f is the frequency; lambda is the wavelength.
*January 13, 2013*

**Machanics**

vf - vi = 5*10^6 - 2*10^6 = 3*10^6 where vf is the final speed and vi is the initial speed. Assuming a constant deceleration, the electron passes through 2.1 multiply 4cm = 8.4 cm of paper. 8.4 = 1/2*a*t^2 deltav = 3*10^6 = a*t where a is the acceleration, t is the time. You ...
*January 13, 2013*

**Physics**

525 - 413
*January 13, 2013*

**Physics**

You are not going to die. You just might not get the right answer.
*January 13, 2013*

**physics**

Use conservation of momentum. In the x direction: 0.02*5.5 = 0.02*vA*cos(65) + 0.04*vB*cos(37) In the y direction: 0 = 0.02*vA*sin(65) - 0.02*vB*sin(37) You should be able to use algebra to solve for these equations, since you have two equations with 2 unknowns; vA is the ...
*January 13, 2013*

**physics**

F(q2) = ke*q1*q2/(r12)^2 + ke*q3*q2/(r23)^2 = 0 or q1*q2/(r12)^2 = q3*q2/(r23)^2 q*-2q/(r12)^2 = 3q*-2q/(r23)^2 -2*q^2/(r12)^2 = -6q^2/(r23)^2 or 1/(r12)^2 = 3/(r23)^2 where r12 is the distance between charge 1 and 2; r23 is the distance bewteen charge 2 and 3. For symmetry ...
*January 13, 2013*

**Physics**

deltaL = a*L*deltaT where deltaL is the change in length, a s the linear expansion coefficient, L0 is it's initial length, deltaT is the final temperature deltaL = 10^-5*178*(-35 - 39)
*January 9, 2013*

**math**

N = (1 + E)^12 -1 where N is the nominal interest rate per year; and E is the effective monthly interest rate per year. For Ally Bank, (N+1)^10 = 1.25 Use this equation to solve for N: N+1 = log10(1.25) N = log10(1.25) - 1 Then use the first equation to find E
*January 8, 2013*

**math (calculate speed)**

m*g*h = 1/2*m*v^2 where m is the mass; g is the acceleration due to gravity; v is the speed. At the top of his dive, the swimmers energy is entirely potential energy = m*g*h; When he enters the pool, the potential energy is converted to kinetic energy: 1/2*m*v^2 v = = (2*g*h)^0.5
*January 8, 2013*

**Math**

-3*y + 2*x = -12 multiply both sides by a negative 1: 3*y - 2*x = 12 3*y = 12 + 2*x y = 2/3x + 4 This is an equation of a line with slope 2/3; y intercept = 4; Graph this equation; the graph of this line is the solution to this equation
*January 8, 2013*

**Physics, waves**

v = (T/mu)^0.5 where v is the speed, T is the tension, and mu is the linear density v = lamda*f ; lambda = 2*L for the fundamental mode, where f is the frequency, and lambda is the wavelength f = (1/(2*L))*(T/mu)^0.5 1.61 g = 0.00161 kg mu = 0.00161/0.64 200 = (1/(2*0.64))*(T/...
*January 8, 2013*

**science, physics**

The total energy is entirely kinetic energy as the block passes through the equilibrium position E = 1/2*m*v^2 where m is the mass, and v is the velocity
*January 8, 2013*

**Physics**

9.4 cm = 0.094 m x = -0.094*cos(w*t) v = dx/dt = 0.094*sin(w*t) where w = (k/m)^0.5 x is the x position; v is the speed; w is the angular velocity; k is the spring constant; m is the mass at t = 0.24 s, v = 0.094*sin(((2080/0.46)^0.5)*0.24)
*January 8, 2013*

**math**

Her expectation of winning is 1%. The fair value is $200/100 = $2.00
*January 8, 2013*

**maths**

Let the rate at which A works be a; the rate at which B works be b; the rate at which C work be c: (a + b)*12 = 1 (b + c)*15 = 1 a = 2*c gives b + a/2 = 1/15 b = 1/15 - a/2 Substituting into the first equation: (a + 1/15 - a/2)*12 = 1 a/2 + 1/15 = 1/12 a/2 = 1/12 - 1/15 = (15-...
*January 8, 2013*

**algebra**

Plot the points (140, 1.4); (150, 1.25); (170, 0.93); (175, 0.78); (205, 0.43) on your graphing calculator; Use your calculator manual to find out how to fit this data to a straight line (linear model), and then a quadratic equation (quadratic model) Look at the results; which...
*January 8, 2013*

**Physics**

The velocity of the passenger is (50-3) = 47 m/s East
*January 7, 2013*

**Social Studies**

Summarize the major factors that allowed the Incas to conquer and rule their large empire. Some suggest that, in many ways, the Incas were like the Romans or other Pre-Columbian American Civilizations. Evaluate whether they were more similar or different, and why. Make sure to...
*January 6, 2013*

**calculus**

solve the following logarithmic equation. Be sure to reject any value of x that is not in the domain of orginal expression. then in the solution set round to two decimals places. Inx=8 I get e^8 But am having a hard time with rounding two decimal places. Can someone help?
*January 1, 2013*

**calculus**

Thanks for telling me how to actually write it here.
*December 31, 2012*

**calculus**

solve the following exponential equation. exact answers only 1-8x 3x ¨i =e *I know that I did not post this correctly but I do not know how to put the 1-8x above the pie symbol and 3x above the e.
*December 31, 2012*

**calculus-can someone please help me with this ques**

I have two questions if someone can PLEASE help. 1.solve the equation in the real number system. x^4+11x^3+24x^2-23x+35=0 **Please show work** 2.Use the remainder theorem to find the remainder. When f(x)is divided by x-3. Then use the factor theorem to determine whether x-3 is...
*December 30, 2012*

**math**

Using the best-fit line below for prediction, answer the following questions: a) What would you predict the price of Product X in volume of 150 to be (approximately)? b) What would you predict the price of Product X in volume of 100 to be (approximately)?
*December 29, 2012*

**Physics **

What is the frictional force between the tires of a 2000 kg car and an asphalt road if the coefficient of friction is 1.2?
*December 20, 2012*

**Physics**

If the coefficient of kinetic friction between a 36 kg crate and the floor is 0.31, what horizontal force is required to move the crate at a constant velocity (so that FNET=0.0 N) across the floor?
*December 20, 2012*

**Physics **

What is the frictional force between the tires of a 2000 kg car and an asphalt road if the coefficient of friction is 1.2?
*December 20, 2012*

**Physics**

Look up the density of saltwater and the density of fresh water. The ship will sit higher in the liquid with greater density. The density of the water displaced times the volume of the water displaced is equal to the weight of the ship. A fluid with a greater density will ...
*December 18, 2012*

**maths**

Let the new point be (x1, y1, z1) Then, using the distance formula: ((x1-1)^2 + (y1-3)^2 + (z1-3)^2)^0.5 = 5 (x1-1)^2 + (y1-3)^2 + (z1-3)^2 = 25 Put all units in terms of one variable. I'm choosing x1 first: x1+2/3 = y1+1/2; y1 = x1 + 2/3 - 1/2 = x1 + 1/6 x1 + 2/3 = z1-3/2...
*December 18, 2012*

**math**

For the square with area 25 yd^2, x^2 = 25; x = 5; where x is the length of a side of the square. The perimeter of this square is 5*4 = 20 For the square with area 5 yd^2, y^2 = 5; y = 5^0.5; where y is the length of the side of this square. The perimeter of this square is 4*(...
*December 18, 2012*

**chemistry**

pH = -log[H+] pOH = -log[OH-] and pH = pOH = 14 pOH = -log(0.01) = 2 2 + pH = 14; pH = 12
*December 18, 2012*

**C++**

This is a perfect opportunity for you to develop the skill of reading your textbook and finding the necessary information. You will probably need to find functions that read and search data, separate data into components, and store data. Find these functions, and read through ...
*December 18, 2012*

**science**

Available is a 5 M/liter solution. You need 100 mL of a 0.91 M solution. In units of moles, you need 0.91 mol/liter * 0.1 liter = 0.091 moles of HNO3 0.091 moles / (5moles/liter) = 0.0182 liters of the 5 M solution. Take 0.0182 liters of the 5 M solution, and dilute to 100 mL...
*December 17, 2012*

**Calculus**

V = 4/3*PI*r^3 dV/dt = 12 = 4*PI*r^2*dr/dt = 4*PI*1^2*dr/dt Solve for dr/dt, the rate at which the radius is growing
*December 17, 2012*

**help math**

vboat + vcurrent = 23/3.6 vboat - vcurrent = 23/3 where vboat is the speed of the boat without a current, v is the speed of the current. The first equation models the boat traveling with the current; the second equation models the boat traveling against the current. Use ...
*December 17, 2012*

**Algebra 2**

graph the function on your graphing calculator. The domain is the set of x values for which the function is defined; the range is the set of y values. Look at the graph and determine the set.
*December 17, 2012*

**physics**

deltaQ = 0; where Q = m*C*T m is the mass, C is the specific heat, T is the temperature 608*C*(Tf-77) + 429*C*(Tf-23) = 0 Where Tf is the final temperature Solve for Tf
*December 17, 2012*

**Calculus**

The boundaries for phi are 0 to 2*PI The boundaries for theta are 0 to PI
*December 16, 2012*

**physics**

Q = m*C*(Tf-Ti) where Q is the heat, m is the mass of the substance, C is the specific heat, Tf is the final temperature; Ti is the initial temperature. deltaQ = 0 or 5*C(Tf - 10) + 1*C*(Tf - 40) = 0 divide by C: 5*(Tf-10) + (Tf-40) = 0 Solve for Tf.
*December 16, 2012*

**statistics**

a) 160 males answered the survey; and 110/160 = 68.75% preferred the current schedule. 140 females answered the survey, and only 50/140 = 35.71% preferred the current schedule, and 90/140 preferred the flex schedule b) One way of describing the preferences is that males are ...
*December 16, 2012*

**physics**

angular momentum of a hoop is m*r^2; the angular momentum of a solid cylinder is 1/2*m*r^2; the angular momentum of a solid sphere is 2/5*m*r^2; the Angular momentum of a hollow spherical shell is 2/3*m*r^2
*December 15, 2012*

**physics**

Volume of air in the balloon = V =(4/3)*PI*r^3 = (4/3)*PI*0.5^3 mass of air displaced is 1.29 * V mass of helium is 0.181*V Upward force due to pressure difference between helium and air is (1.29 - 0.181)*V Sum of forces in the y direction is 0: (1.29 - 0.181)*V - T - 0.0120...
*December 15, 2012*

**Physics**

F = -k*x where F = force, x is displacement 70.4 = -k*0.0535
*December 14, 2012*

**physics**

F*x = 1/2*m*v^2 where F is the average force, x is the distance over which the bullet is accelerated, v is the speed, m is the mass of the bullet F*0.432 = 1/2*22*907^2
*December 14, 2012*

**Physics**

Power = F*v where F is the force, v is the speed 53.3 = F * (1.32m/1.22s)
*December 14, 2012*

**Math**

Evaluate each of these answers: For example, evaluate A. (-1/2)^4 + 7*(1/2)^2 - 9*(1/2) -1 and 0^4 + 7*0^2 - 9*0 -1 If one of these answers is negative and one of these is positive, then the Intermediate Value Theorem guarantees taht the polynomial has a root in this interval...
*December 14, 2012*

**Algebra 1- Math**

a. At the start, months = 0; employees = 2. In 6 months, months = 6; employees =14 (0,2) (6,14) b and c. 2 employees/month is the slope This is how many employees the company would have to add per month to get 14 employees at the end of 6 months E = 2 + r*m where E is the ...
*December 14, 2012*

**Chemistry**

MnO4−(aq) + SO32−(aq) + H+(aq) → Mn2+(aq) + SO42−(aq) + H2O(l) in the form a*MnO4−(aq) + b*SO32−(aq) + c*H+(aq) → d*Mn2+(aq) + e*SO42−(aq) + f*H2O(l) Start by counting how many of each are on each side. I'm going to choose to...
*December 14, 2012*

**Algebra 2**

B = P*e^(Yr) where B is balance, P is principle = 1600; e is the number e; Y is the number of years; and r is the rate 0.079 Plug these numbers in and solve for the answer.
*December 14, 2012*

**physics**

Start the person at (0,0), and calculate the new position after each path. After path 1: (80,0) After path 2: (80, -250) After path 3: x displacement is -130*cos30; y displacement is -130*sin30 (80 - 130*cos30, -250 -130*sin30) After path 4: x displacement is -190*cos30, y ...
*December 13, 2012*

**math**

How many squares are on each side? x*y = 49 where x the number of squares for the width, and y is the number of squares for the length. 120000 = X*Y where X is the width in feet, Y is the length in feet 120000/49 = (X/x) * (Y/y) You have X/x = Y/y
*December 13, 2012*

**Math help give example**

Third degree means that it has one term to the power of three. One example: x^3 + x^2 + x + 1
*December 13, 2012*

**business**

Look up how the vehicle should be serviced -- i.e., checkup every 5000 miles? etc. Determine the best method of doing so--consider all options available, such as hiring one person to do the job, scheduling periodic checkups at a repair shop, etc.
*December 13, 2012*

**Math help storie problem**

let g be the price of green peppers and r be the price of red peppers. 3*g + 2*r = 3.45 4*g + 3*r = 5.00 Use algebra to solve for g and r
*December 13, 2012*

**calculus**

The derivative of sinh(x) is cosh(x), and the derivative of cosh(x) is sinh(x) So the nth derivative of sinh(x) is cosh(x) if n is odd; and the nth derivative of sinh(x) is sin(x) if n is even The nth derivative of cosh(x) is sinh(x) if n is odd; and the nth derivative of cosh...
*December 12, 2012*

**Physics**

rho1*V1 = rho2*V2 where rho1 is the density of the object; V1 is the volume of the ship; rho2 is the density of the water; V2 is the volume of the water mass of object = 0.97 106/g = 0.97 106/9.8 density of object = 0.97 106/(9.8*0.03*A) where A is the area (0.97 106/(9.8*0.03...
*December 12, 2012*

**geometry**

Determine the approximate midpoint of all the areas serviced, both in terms of distance, and with respect to traffic speed limits, road conditions, etc.
*December 12, 2012*

**College Algebra**

x*y = 480 2x + 2y = 88 solve for x and y, the width and length
*December 12, 2012*

**Physics**

v = v0 - 1/2*g*t^2 where v is speed as a function of time, v0 is the inital speed, and g is the acceleration due to gravity v = 24 - 4.9*t^2 = 0 Solve for t When it returns to its starting point, the time will be 2*t, using t from the first question. Calculate v at this time (...
*December 12, 2012*

**geometry**

tan 60 = 120/x; x = 120/tan60
*December 12, 2012*

**Chemistry..**

London dispersion force is a weak intermolecular force between two atoms or molecules in close proximity of each other. The force is a quantum force generated by electron repulsion between the electron clouds of two atoms or molecules as they approach each other. The London ...
*December 12, 2012*

**Math**

A = P *r*((1+r)^n)/((1+r)^n-1) where A = payment Amount per period P = initial Principal (loan amount) r = interest rate per period n = total number of payments or periods n = 30*12 = 360 P = 250000 4 = 0.045 A = 250000*0.045 * (1.045^360)/(1.045^360 - 1)
*December 12, 2012*

**Physic**

The tungsten filament emits white light, or the entire spectrum of colors of light. (look at any light bulb when its on). When the light is viewed with a spectroscope, it separates the white light into the different colors.
*December 11, 2012*

**math**

The formula for calculating the payment amount is shown below. A = P * ((r(1+r)^n)/(((1+r)^n)-1) Simple Amortization Calculation Formula where A = payment Amount per period P = initial Principal (loan amount) r = interest rate per period n = total number of payments or periods...
*December 11, 2012*

**statistics**

The probability of this combination occurring is (0.23^175) * (0.77 ^625)
*December 11, 2012*

**Math**

Δx/3*[f(x0)+4f(x1)+2f(x2)+4f(x3)+........+2f(xn−2)+4f(xn−1)+f(xn)] = 30/3 * (76 + 4*118 + 2*130 + 4*143 + 2*139 + 4*136 + 2*137 + 4*139 + 2*130 + 4*122 + 60)
*December 11, 2012*

**Chemistry**

The density of maple syrup is 1.33g/mL. a bottle of maple Syrup contains 740mL of syrup. What is the mass of maple syrup?
*December 11, 2012*

**geometry**

An arrow pointing to the bottom left
*December 10, 2012*

**math**

I think that you graph both; if you were asked to graph f>3 AND f< -2, there would be nothing to graph, because there is no intersection of the graphs. But because the selector is OR, you graph all the points for which f>3 (y > 3) or f<-2 (y<-2)
*December 10, 2012*

**math**

2*2*2
*December 10, 2012*

**Physics**

Using conservation of momentum: 2*8 + 4.8*2.8 = (2+4.8)*vf = 6.8*vf Solve for vf, the final speed of the blocks when they have the same velocity. 1/2*k*x^2 = 1/2*m*vf^2 Solve for x; k is the spring constant = 1180 N/m; x is the maximum compression of the spring
*December 10, 2012*

**MATH**

Convert each number to a whole fraction: 4 5/7 = (4*7 + 5)/7 = (28+5)/7 = 33/7 3 2/3 = (3*3 + 2)/3 = (9 + 2)/3 = 11/3 33/7 / 11/3 = 33/7 * 3/11 = (33*3) / (7*11) = 99/77 = (9*11)/(7*11) = 9/7
*December 10, 2012*

**Math**

(x+2)/6 = 3/(x-1) (x+2)*(x-1) = 6*3 = 18 x^2 + 2*x - x -2 = 18 x^2 + x - 20 = 0 (x-4)(x+5) = 0 x = 4 or x = -5
*December 10, 2012*

**math**

4 stripes and 2 colors will make 2*2*2*2 different logos 3 stripes and 2 colors will make 2*2*2 different logos Subtract the two to find the difference
*December 10, 2012*

**Math**

The height at the bottom of the wheel is 2 m; The height at the top is 2 + diameter = 137; The height at the center of the wheel is 2 + radius = 2 + 135/2 The circumference of the London Eye is 2*PI*r = PI*diameter = 135*PI. This is how far a passenger travels as the wheel ...
*December 10, 2012*

**physics**

The resonance frequency is 1/((LC)^0.5) Where L is the inductance = 6 * 10 ^-3 H and C is the capacitance = 2.5 * 10^-6 F
*December 10, 2012*

**physics**

x = 1/2*g*t^2 = 2 = 4.9*t^2 Solve for t, the time then solve for the climber's speed v using v = 9.8*t 1/2*m*v^2 = 1/2*k*xstretch^2; where xstretch is the amount that the rope will stretch
*December 10, 2012*

**Physics ASAP**

Sorry, I can't draw a force diagram of the box. The sum of the forces in the y-direction is zero: N - 20 + 30*sin(37) = 0 Solve for N, the normal force B) The frictional force between the block and the table is defined as µk*N = 0.25*N C) The work done by the ...
*December 10, 2012*

**Physics**

You substitute g of moon for g of earth in the equation; Then do the calculation for g of earth; divide the two to find the ratio.
*December 10, 2012*

**Physics**

Use conservation momentum 0.05*33 = 4.8*v Solve for v, the speed of the launcher
*December 10, 2012*

**physics**

Let F1 and F2 be the forces on the two ends of the bridge. The sum of the forces in the y direction is 0: F1 + F2 - 1120 - 3775 = 0 The sum of the torques about each support is zero: 1120*(L/5) + 3775*(L/2) - F2*L = 0 Dividing by L: 1120/5 + 3775/2 - F2 = 0 Solve for F2, then ...
*December 10, 2012*

**SOCIALS HELP...THANX**

Thank you sooooooo much Rylee. Your a great help! Thanx once again :)
*December 9, 2012*

**SOCIALS HELP...THANX**

This question is based on: the Reign of Terror which government replaced Robespierre and what did that signify for France? Pleese help... Thanx
*December 9, 2012*

**maths --plse help me..**

(a+b+c)^7 = (a+b+c)*(a+b+c)*(a+b+c)*(a+b+c)*(a+b+c)*(a+b+c)*(a+b+c) will be of the form a^7 + c1*a^6*b + c2*a^6*c + c3*a^5*b^2 + c4*a^5*c^2 + c5*a^5*b*c + . . . . where c1, c2, c3 are constants found when doing the actual expansion. so all the terms in the expansion are of the...
*December 9, 2012*

**Physics**

Weight = Lift = Area*(PressureBottom - PressureTop) = (1/2)(air density)*Area*(V2^1 - V1^2) V2 = 63.9 m/s V1 = 58 m/s Look up the air density
*December 8, 2012*

**Chemistry**

27) What volume of benzene (C6H6, d= 0.88 g/mL, molar mass = 78.11 g/mol) is required to produce 1.5 x 103 kJ of heat according to the following reaction? 2 C6H6(l) + 15 O2(g) ¨ 12 CO2(g) + 6 H2O(g) ƒ¢H‹rxn = -6278 kJ
*December 8, 2012*

**Physics**

For small angles, sin theta is approximately equal to tan theta = Y/L = 0.25/2 Calculate the error (0.25/2.01 - 0.25/2)/(0.25/2.01)
*December 8, 2012*

**Chemistry**

Write a balance equation for the reaction of nitric acid (HNO3) with each base solution : [1]. NaHCO3, [2]. MgCO3. ( Please include the phases of the substance)
*December 8, 2012*

**Math**

The slope of the first hill is 17/25. The slope of the 2nd hill is 0.7. Which slope is greater? This is the slope of the steeper hill.
*December 7, 2012*

**Grade 11 MAth**

The midpoint of the range -4 <= y <=1 is y = -1.5 with an amplitude of 2.5 The equation is now of the form: y = 2.5*sin(a*x) - 1.5 When a = 1, the period is 360 degrees. So when a = 45/360; the period will be 45 degrees, or when a = 1/8 y = 2.5*sin(x/8) - 1.5 for the ...
*December 7, 2012*

**pharmacy tech**

convert 164 lb to kg; 5 mg/kg/day * 1day/3doses = 5/3 mg/kg per dose Multiply this number by the weight of the patient in kg
*December 7, 2012*

**math**

let g=green; b=blue; r=red; y=yellow; o=orange This is one example g,b,r,y,o r,y,o,g,b o,g,b,r,y b,r,y,o,g y,o,g,b,r Notice that the order is the same in each line, shifted by 2
*December 7, 2012*

**science**

a. The mass doesn't change; it's still 92 g b. density = mass/volume = 92g/100cm3 c. Is the density of the ice cube less than or greater than the density of water? If it is less than, the ice cube will float. If it is greater than, the ice cube will sink.
*December 7, 2012*

**physics**

the pressures F/A on both pistons should be equal. F = force, A = area 2000/20 = X/1 100 = X ______________
*December 7, 2012*

**math**

3(k-4.8)=0.7(k-6.9) 3*k-3*4.8=0.7*k-0.7*6.9 3k - 14.4 = 0.7k - 4.83 Subtracting 0.7k from each side: 3k -0.7k - 14.4 = 0.7k - 0.7k - 4.83 2.3k - 14.4 = -4.83 Adding 14.4 to each side 2.3k = 9.57 Dividing each side by 2.3: k = 4.16
*December 5, 2012*

**physics**

The bullet goes from rest to a speed of 710 m/s in 2.36 * 10^-3 s v = a*t where v is the speed, a is the acceleration, and t is time 710 = a * 2.36*10^-3 Solve for a Force = m*a where m is mass
*December 5, 2012*

**math**

The total number of answers recorded is 35+35+30 = 100 3 of these answers belong to 1 person: At this point in the problem, person count = 1 answer count = 100-3 - 97 6 used buses as well as their own cars. One of these persons would be the person who used all three; so 5 used...
*December 5, 2012*

**Math**

9 use shampoos A and C. This set of 9 also includes people who would use B. 5 people use all three 9 - 5 = 4
*December 5, 2012*

**math**

140 students owned iPhones; of these 50 also owned cars; 140 - 50 = 90 90 students own only an iphone 60 owned cars; of these 50 also own a car; 60-50 = 10; 10 students own ONLY a car The number of student who own either a car or an iphone, but not both is 90 + 10 = 100 The ...
*December 5, 2012*

**math**

First draw a picture. Split the isosceles triangle down the middle of triangle, bisecting the angle x. Now you have divided the isosceles triangle into two right angled triangles, each with area of 1/2 height * base. So the area of the isosceles is the sum of both of these ...
*December 5, 2012*