Friday

May 22, 2015

May 22, 2015

Total # Posts: 108

**Chemistry**

A solution of NaOH(aq) contains 7.7 grams of NaOH in 93 mL of solution. Calculate the pH at 25◦C. ---- 7.7 grams x (1 mol/39.997 grams) = 0.19 mol 0.19 mol/0.093 L = 2.07 M pOH = -log(2.07) = -0.316 ---- Am I doing anything wrong? Why am I getting a negative pOH/pH ...
*February 11, 2015*

**AP Chemistry**

A saturated solution of CaF2 (of MW 78.0 g/mol) contains 0.0167 grams per liter. What is the solubility product constant of CaF2?
*January 20, 2015*

**math**

Yeah The large rectangle has an area of (3x2)+(3x5)=6+15=21 Factors of 21 1, 3,7, 21 The large rectangle is 3x7
*January 20, 2015*

**math **

The 3rd term in an arithmetic sequence is 12, the 7th term is 24, a) How many common differences are there between a_3 and a_7? b) What is the common difference of the sequence? c) What is the first term in the sequence? a_1 d) What is the expression for this arithmetic sequence?
*May 21, 2014*

**Math**

The solution to f(x)=0 is always the values of x where the graph crosses the x-axis, usually called the x-intercepts. Your graph is a V-shaped graph that crosses the x-axis at x=-4 on the left and at x=4 on the right. So they are the solutions to f(x)=0. Answers: x=-4 and x=+4...
*February 5, 2014*

**Math**

That's the equation of a parabola opening downward, so the vertex will be the highest point on the parabola, and its x-coordinate will be the value of x producing that highest point. The formula for the x-coordinate of the vertex is -b/(2a) = -(300)/[2(-5)] = (-300)/(-10...
*February 4, 2014*

**math**

Round $579 up to $600. Round $85 up to $100. $600-$100 = $500. (Notice that the exact answer = $494, so $500 isn't far off from it, and $500 serves the pupose well when you don't have a calculator or pencil and paper or just don't want to take time to calculate it.).
*February 4, 2014*

**Math**

>>She could paint 5 identical rooms during one 6-hour shift.<< So her painting rate was 5 rooms per 6 hours or (5 rooms)/(6 hours) or (5/6)room/hour How long did she take to paint each room? Let the length of time in hours be x Accomplishment = (Rate)(Time) Since ...
*February 3, 2014*

**English**

Answer A. Rule for writing numbers: Spell out single-digit whole numbers. Use numerals for numbers greater than nine.
*January 23, 2014*

**English**

I would for you to overlook my narrative essay, for corrections and your advice. The essay is not finished, but would like to know am I on the right path. A Painful Moment It was the summer of 1998; I was twenty years old celebrating the 4th of July with my brother the day ...
*October 16, 2013*

**English**

Thank you for over looking my work and giving me confidence. English is not an easy subject for me.
*October 5, 2013*

**English**

How would I revise this sentence to eliminate unnecessary shifts in tense, mood, voice, or person? The freezing weather is threatening crops such as citrus fruits which were sensitive to cold. The freezing weather threatened the crops, which were sensitive to cold.
*October 5, 2013*

**3 grade math**

8 boxes of 1000 counters
*August 22, 2013*

**maria vazquez**

Sonoma winery has fixed cost of $10,000 per year. its warehouse sells wine with variable costs of 80% of its unit selling price. How much in sales does Sonoma need to break even per year?
*April 29, 2013*

**science**

Which of the following would require more energy to heat it from 10°C to 20°C? a. 200 kg of water b. 200 kg of aluminum c. 100 kg of steel How much heat energy is required to raise the temperature of 20 kilograms of water from 0°C to 35°C?
*February 7, 2013*

**3rd Grade Math**

Suppose the teacher says to the class: "We're going to play a game and to play it we must have exactly the same number of boys as we have girls. So 9 of you boys will have to go to another room while we play this game." So 9 boys get up and leave the room. That ...
*October 2, 2012*

**Math**

yes this is off a take home test
*September 16, 2012*

**english 3 grade**

aphabet on move words
*August 29, 2012*

**Science**

Based on your knowledge of the relationship between photosynthesis and CO2, explain why CO2 concentrations cycle throughout the year.
*May 7, 2012*

**physics**

It will not be answered in units of k. It is asking for a force, so the units will be in Newtons. (I assume you meant "kN", which would be kiloNewtons.) The forces acting on the pilot at the bottom of the loop are gravity and the normal force. However, they are ...
*December 12, 2011*

**law**

How has the feminist movement influenced criminology? What negative impact has resulted from feminism, if any?
*December 4, 2011*

**law**

What are the policy implications of social development theories? How have these implications been reflected in actual policy, if at all?
*December 4, 2011*

**business**

what does multi-tier supplier mean?
*November 23, 2011*

**business**

Many organizations find themselves in the apparently contradictory position of having high levels of financial investment in inventory, but at the same time frequently running out of stock of important components and materials. (a) explain how this situation could arise. (b) ...
*November 21, 2011*

**social studies**

what are the main assumptions underlying organizational communication?
*November 18, 2011*

**business**

i think the supply chain driver is the supplier. And is related to supply chain focus by supplying raw materials to manufacturers who produce finished products. Then the supplier supplies the finished products to wholesalers. My lecturer said i was out of point! It was a ...
*November 18, 2011*

**business**

define a supply chain driver and show it's relation to supply chain focus with a couple of examples
*November 18, 2011*

**Social studies**

In what year did Napoleon lead the battle of waterloo?
*October 1, 2011*

**MATH**

@psydag, sorry for shouting @mathmate, thanks for the solution thank you edwin
*June 15, 2011*

**MATH**

WRITE A SIMPLE BUT A COMPLETE FORTRAN PROGRAM TO CALCULATE THE AREA OF A TRIANGLE
*June 15, 2011*

**MATH**

WRITE A SIMPLE BUT A COMPLETE FORTRAN PROGRAM TO COMPUTE THE AVERAGE OF SIX NUMBERS AND DISPLAY THE NUMBERS, SUM AND AVVERAGE. THE PROGRAM SHOULD TERMINATE WHEN ZERO IS ENTERED AS A NUMBER. THE PROGRAM SHOULD BE EDUCATIVE
*June 15, 2011*

**MATH**

thanks mathmate for your response. we were asked to use WATFOR77 compiler.i'm a newbee as far as programming is concern. can you pls. write the program the way i can run it in WATFOR77? thanks edwin
*June 15, 2011*

**MATH**

FORTRAN ROGRAM THAT CAN ACCEPT TWO INTEGER NUMBERS AND COMPUTE AND DISPLAY ALL THEIR COMMON PRIME FACTORS
*June 15, 2011*

**math**

please can u help me for my homework thanks a lot the question is below.. A container is 1/3 full of water and 1/4 full of oil. What fraction of the container is empty?
*February 13, 2011*

**College Algebra**

3x^2-12x-24=0
*February 2, 2011*

**statistics**

A study was conducted to investigate the relationship between the cost, y (in tens of thousands of dollars), per unit of equipment manufactured and the number of units produced per run, x. The resulting equation for the line of best fit is given below, with x being observed ...
*December 6, 2010*

**geometry**

show that points (3,-1) (4,2) (1,3) and (-2,-1) the vertices kite-shaped quadrilateral find its area
*October 28, 2010*

**Physics **

Sorry typo I meant 180 g apple, I am really sorry
*October 24, 2010*

**Physics **

Yep its me again... sorry for re-posting this question but I am quite desperate here and I need to have this question answered, sorry if that sounds rude. IF 2.0 J of work is done raising g apple how far is it lifted? I know W= Fd hence I divided instead of multiplying and I ...
*October 24, 2010*

**Physics (Checking answe)**

Sorry for re-posting but I need to know if I did it right, please help, I worked out the problem I just want to know if I did it right. A shopper in a supermarket pushes a cart with a force of 35 N directed at an angle of 52(angle sign here) downward from the horizontal. Find ...
*October 24, 2010*

**Physics**

A shopper in a supermarket pushes a cart with a force of 35 N directed at an angle of 52(angle sign here) downward from the horizontal. Find the work done by the shopper on the cart as the shopper moves along a 50.0 m length of aisle. Someone tell me if this is right: W= (35....
*October 24, 2010*

**MATH**

given ax^2 +bx +c=0. one root is square of the other, without solving the expression proove that: c(a-b)^3 = a(c-b)^3
*October 1, 2010*

**Math**

5^(k+1) - 1 =4(m+1)
*May 12, 2010*

**math**

A straight line AB of length 10 units is free to move with its ends on the axes. Find the locus of a point P on the line at a distance of 3 units from the end on the x axis.
*April 30, 2010*

**physics**

Three charges of 5 x 10^(-6) C are placed on the vertices of an equilateral triangle of 10cm. Calculate force on each charge.
*April 5, 2010*

**physics**

A clean glass capillary tube is held vertically in water raised to a height of 7cm. The tube is down depressed and only 5cm of its length is above water. What will be the angle of contact?
*March 29, 2010*

**physics**

A clean glass capillary tube is held vertically in water raised to a height of 7cm. The tube is down depressed and only 5cm of its length is above water. What will be the angle of contact?
*March 28, 2010*

**physics**

A clean glass capillary tube is held vertically in water raised to a height of 7cm. The tube is down depressed and only 5cm of its length is above water. What will be the angle of contact?
*March 28, 2010*

**physics**

Show that a force acting along a given line can always be replaced by a force of the same magnitude acting along a parallel line, together with a couple.
*March 28, 2010*

**physics**

a fluid flows through a horizontal pipe of varying cross-section. Assuming the flow is streamline and applying the bernoulli equation, show that pressure in the pipe is greatest where cross-sectional area is greatest.
*March 28, 2010*

**physics**

a fluid flows through a horizontal pipe of varying cross-section. Assuming the flow is streamline and applying the bernoulli equation, show that pressure in the pipe is greatest where cross-sectional area is greatest.
*March 28, 2010*

**physics**

If the amplitudes of the two waves are 3 units and 1 unit respectively, show by the principle of superposition that the ratio of the amplitudes of the stationary wave at an antinode and node respectively 2:1
*March 28, 2010*

**physics**

A light rigid bar is suspended horizontally from two vertical wires, one of steel and one of brass. Each wire is 2.00m long. The diameter of the steel wire is 0.60mm and the length of the bar AB is 0.20m. When a mass of 10.0kg is suspended from the centre of AB the bar remains...
*March 28, 2010*

**physics**

A special prototype model aeroplane of mass 400g has a control wire 8cm long attached to its body. The other end of the control line is attached to a fixed point. When the aeroplane flies with its wings horizontal in a horizontal circle, making one revolution every 4 s, the ...
*March 28, 2010*

**physics**

A ball is dropped from a height of 20m and rebounds with a velocity which is 3/4 of the velocity with which it hit the ground. What is the time interval between the first and second bounces?
*March 28, 2010*

**physics**

An open tank holds water 1.25 m deep. If a small hole of cross section area 3cm^2 is made at the bottom of the tank, calculate the mass of water per second initially flowing out of the hole. (g=10m/s^2, density of water= 1000 kgm^-3)
*March 27, 2010*

**physics**

A special prototype model aeroplane of mass 400g has a control wire 8cm long attached to its body. The other end of the control line is attached to a fixed point. When the aeroplane flies with its wings horizontal in a horizontal circle, making one revolution every 4 s, the ...
*March 27, 2010*

**physics**

A light rigid bar is suspended horizontally from two vertical wires, one of steel and one of brass. Each wire is 2.00m long. The diameter of the steel wire is 0.60mm and the length of the bar AB is 0.20m. When a mass of 10.0kg is suspended from the centre of AB the bar remains...
*March 27, 2010*

**physics**

A small piece of cork in a ripple tank oscillates up and down as ripples pass it. If the ripples travel at 0.20m/s, have a wavelength of 15mm and an amplitude of 5.0mm, what is the maximum velocity of the cork?
*March 27, 2010*

**physics**

In the design of a passenger bus, it is proposed to derive the motive power from the energy stored in a flywheel. The flywheel, which has a moment of inertia of 4.0 x 10^2 kgm^2, is accelerated to its maximum rate of rotation 3.0 x 10^3 revolutions per minute by electric ...
*March 27, 2010*

**physics**

Show that a force acting along a given line can always be replaced by a force of the same magnitude acting along a parallel line, together with a couple.
*March 26, 2010*

**physics**

water flows along a horizontal pipe of cross-sectional area 48cm^2 which has a constriction of cross-sectional area 12cm^2 at one place. If the speed of the water at the constriction is 4 m/s, calculate the speed in the wider section. The pressure in the wider section is 1.0 x...
*March 26, 2010*

**physics**

A beam of electromagnetic waves of a wavelength 3.0cm is directed normally at a grid of metal rods, parallel to each other and arranged vertically about 2.0cm apart. Behind the grid is a reciever to detect the waves. It is found that when the grid is in this position, the ...
*March 26, 2010*

**physics**

A progressive and a stationary simple harmonic wave each have the same frequency of 250Hz and the same velocity of 30m/s. Calculate (i) the phase difference between two vibrating points on the progressive wave which are 10cm apart. (ii) the distance between nodes in the ...
*March 26, 2010*

**physics**

Show that a force acting along a given line can always be replaced by a force of the same magnitude acting along a parallel line, together with a couple.
*March 26, 2010*

**physics**

water flows along a horizontal pipe of cross-sectional area 48cm^2 which has a constriction of cross-sectional area 12cm^2 at one place. If the speed of the water at the constriction is 4 m/s, calculate the speed in the wider section. The pressure in the wider section is 1.0 x...
*March 26, 2010*

**physics**

If the amplitudes of the two waves are 3 units and 1 unit respectively, show by the principle of superposition that the ratio of the amplitudes of the stationary wave at an antinode and node respectively 2:1
*March 26, 2010*

**physics**

A flywheel of moment of inertia 0.32 kgm^2 is rotated steadily at 120rad/s by a 50 W electric motor. (i)find the kinetic energy and angular momentum of the flywheel. (ii) calculate the value of frictional couple opposing the rotation. (iii)find the time taken for the wheel to...
*March 26, 2010*

**physics**

Water flows steadily along a uniform flow tube of cross-section 30cm^2. The static pressure is 1.20 x 10^5 Pa and the total pressure is 1.28 x 10^5 Pa. Calculate the flow velocity and the mass of water per second flowing past a section of the tube. (density of water= 1000 kg/...
*March 26, 2010*

**physics**

A small source O of electromagnetic waves is placed some distance from a plane metal reflector M. A reciever R, moving between O and M along the line normal to the reflector, detects successive maximum and minimum readings on the meter joined to it. (a) explain why these ...
*March 26, 2010*

**physics**

A plane progressive wave is represented by the equation: y= 0.1sin(200pi(t)-20pi(x/17) where y is the displacement in millimetres, t is in seconds and x is the distance from a fixed origin O in metres. Find (i) the frequency of the wave, (ii) its wavelength (iii) its speed, (...
*March 26, 2010*

**physics**

The static pressure in a horizontal pipeline is 4.3 x 10^4 Pa, the total pressure is 4.7 x 10^4 Pa, and the area of cross-section is 20cm^2. The fluid may be considered to be incompressible and non-viscous and has a density of 10^3 kg/m^3. Calculate (i) the flow velocity in ...
*March 26, 2010*

**physics**

A flywheel with an axle 1.0cm in diameter is mounted in frictionless bearings and set in motion by applying a steady tension of 2N to a thin thread wound tightly round the axle. The moment of inertia of the system about its axis of rotation is 5.0 x 10^-4 kgm^-2. Calculate (a...
*March 26, 2010*

**physics**

Find (a) the potential and (b) the field strength at points A and B due to two small spheres X and Y 1.0m apart in air and carrying charges of +2.0x10^-8C and -2.0x10^-8C respectively.
*March 24, 2010*

**math**

Find the vector eqn which passes through (1,1,2) and is parallel to the vector which is perpendicular to both 2i+2j-k and -3i+2j+k
*March 24, 2010*

**science**

how to write a program to compute account name, account number and either employed in basis of permanent or cashier labour
*March 24, 2010*

**physics**

A clean glass capillary tube is held vertically in water raised to a height of 7cm. The tube is down depressed and only 5cm of its length is above water. What will be the angle of contact?
*March 23, 2010*

**physics**

A vibrator attached and resting on the surface of water generates plane water waves and its propagation is found to take 50 seconds to reach a floating cork 65 cm away. If the cork subsequently vibrates with SHM of a period 3.8 seconds, determine the wavelength of the water ...
*March 23, 2010*

**physics**

A plane progressive wave on a water surface is given by the equation y=2sin2pi(100t-x/30) where x-is the distance covered in a time t, x, y and t are cm and second respectively. Find (i) the wavelength and frequency of the wave motion. (ii) the phase difference between two ...
*March 23, 2010*

**physics**

What vibrates in the following types of wave motions (i) light waves. (ii) sound waves. (iii) x-rays.
*March 23, 2010*

**physics**

A plane sound wave propagated in air has individual particles which execute a periodic motion such that their displacement y from their rest position at any time t is y=5x10^(-6)sin(800pie(t)+theta). Calculate (i) wavelength. (ii) phase diff in degree between particles 17cm ...
*March 22, 2010*

**physics**

A bird of mass 0.8kg hovers upwards by beating the mass of effective area 0.5m^2. (i) what is its upthrust? (ii) estimate the velocity imparted to the air by beating of the wings assuming the density of air at STP to be 1.3kg/m^3.
*March 22, 2010*

**physics**

A 24V battery of internal resistance of 10ohms is connected to a variable resistor. At what value of current drawn from battery the rate of heat produced by the resistor is maximum? Hence find its value.
*March 16, 2010*

**physics**

The electrical motor runs on a D.C source of emf E and internal resistance r. Show that power output of the motor is max where current drawn by the motor is E/2r.
*March 16, 2010*

**physics**

A silver wire has resistance of 2.1ohms at 27.8 degree celsius and resistance of 2.8ohms at 98 degree celsius. Determine the temperature coefficient of resistance of silver wire and its resistance at zero deg.
*March 16, 2010*

**Physics**

Two spheres S1 and S2 of the same metal and having the same type of surface, have radii 20cm and 10cm respectively. Compare their rates of fall of temperature as they cool (a) when S1 is at 50 degree centigrade, S2 is at 40 degree centigrade, the surroundings are at 20 degree ...
*March 14, 2010*

**Physics**

24 kg of water are heated by a thermostatically controlled 4Kw electric heater. The thermostat switches the heater on at 60 degree centigrade and off at 65 degree centigrade. If the time between switching off and switching on is 3.0 min, what will be the time between switching...
*March 14, 2010*

**Physics**

The heat capacity of a mercury thermometer is approximately equal to the volume immersed in metre cube multiplied by a constant x. If the densities of glass and mercury are 2.40 x 10^3 kgm^-3 and 1.36 x 10^4 kgm^-3 and their specific heat capacities are 800Jkg^-1k^-1 and ...
*March 14, 2010*

**physics**

The density of nitrogen at STP is 1.25 kgm^-3. Find the r.m.s velocity of nitrogen molecule at 20 degree centigrade.
*March 13, 2010*

**Math**

1 25 25 5 50 1 1 10 10
*February 24, 2010*

**physics**

a 1200 kg car going 30 m/s applies its brakes and skids to rest. if the friction force between the sliding ires and the pavement is 6000 N, how far does the car skid before coming to rest. I know the ans is 90 m what work/energy formula should i use to get this answer? can you...
*February 11, 2010*

**College Physics**

A 1200-kg car going 30 m/s applies its brakes and skids to rest. If the friction force between the sliding tires and the pavement is 6000 N, how far does the car skid before coming to rest? Can you help me get the formula to use . Thanks
*February 11, 2010*

**11th grade**

Yes, y=-2 is the equation of the line that contains all the points which have their y-coordinates as -2, such as (3,-2), (5,-2), (-4,-2), etc. Plot those. You'll see that they all lie on a horizontal line which is 2 units below the x-axis. That line is the graph.
*February 11, 2010*

**calculus**

evaluate tan^2 3.658 I know the answer is .322 but I don't know how to arrive at the answer.
*February 6, 2010*

**Spanish**

Don't understand differences between lo, la, le
*January 28, 2010*

**math**

(b) the digits of a positive integer having three digits are in A.P and their sum is 15. The number obtained by reversing the digits is 594 less than the original number. Find the number. (c) if a,b,c are in A.P, prove that (i) (ab)^-1, 1/ac, 1/bc are also in A.P. (ii) a(b+c...
*September 23, 2009*

**math**

(b) the digits of a positive integer having three digits are in A.P and their sum is 15. The number obtained by reversing the digits is 594 less than the original number. Find the number. (c) if a,b,c are in A.P, prove that (i) (ab)^-1, 1/ac, 1/bc are also in A.P. (ii) a(b+c...
*September 23, 2009*

**business**

According to the Uniform Partnership Act, the three key elements of any general partnership are
*September 16, 2009*

**understanding business**

is the most important step to help improve America's business ethics?
*September 16, 2009*

**accounting**

Sandusky Inc. has the following costs when producing 100,000 units: Variable Costs $400,000 Fixed Costs 600,000 An outside supplier is interested in producing the item for Sandusky. If the item is producing outside, Sandusky could use the released production facilities to ...
*March 14, 2009*