Popular questions and responses by Phil
  1. Physics

    A guitar string is 90cm long and has a mass of 3.8g . The distance from the bridge to the support post is L=62cm , and the string is under a tension of 540N . What are the frequencies of the fundamental and first two overtones?

    asked on January 25, 2013
  2. algebra

    using formula d(h)=8e^-0.4h to determine the milligrams d of a certain drug in bloodstream h hours after many milligrams will be present after 6 hours?

    asked on July 17, 2013
  3. Physics- PLEASE HELP

    Two boxes of fruit on a frictionless horizontal surface are connected by a light string as in the figures below, where m1 = 15 kg and m2 = 17 kg. A force of 58 N is applied to the 17 kg box. Repeat the problem for the case where the coefficient of kinetic

    asked on October 3, 2012
  4. Physics

    Figure (a) shows charged particles 1 and 2 that are fixed in place on an x axis. Particle 1 has a charge with a magnitude of |q1| = 12.0e. Particle 3 of charge q3 = +13.0e is initially on the x axis near particle 2. Then particle 3 is gradually moved in

    asked on January 20, 2012
  5. History

    How did the geographic location of Philadelphia affect the city's development? Because of its location on rivers, the city built bridges and used ferries to allow workers to access the city. Because of proximity to water, streets had to be properly

    asked on April 25, 2017
  6. chemistry

    Standard Addition Question: Serum containing Na+ gave a signal of 4.27 mV in an atomic emission analysis. Then 5.00 mL of 2.08 M NaCl were added to 95.0 mL of serum. This spiked serum gave a signal of 7.98 mV. Find the original concentration of Na+ in the

    asked on August 9, 2015
  7. Science URGENT help please

    Piano movers hoist a 200 kg piano 10 m high in 30 s using a rope and simple pulley. What is their power output? (Points : 1) 70 W 700 W 7,000 W 6 × 10^5 W

    asked on April 16, 2014
  8. English

    Mr. Smith, my Spanish teacher, is going on vacation. is this correct PUNCTUATION AND GRAMMER

    asked on December 31, 2012
  9. Physics

    A 13 cm long animal tendon was found to stretch 3.8 mm by a force of 13 N. The tendon was approximately round with an average diameter of 9.0 mm. Calculate the elastic modulus of this tendon.

    asked on October 28, 2010
  10. physics

    A wooden box weighing 271 N is pushed across the floor by a workman who exerts a horizontal force of 144 N. If the force of friction between the box and the floor is 28 N, what is the acceleration (in meters/second^2) of the box?

    asked on March 7, 2012
  11. Physics

    The coefficient of kinetic friction for a 22 kg bobsled on a track is 0.15. What force is required to push it down a 6.0° incline and achieve a speed of 64 km/h at the end of 75 m?

    asked on October 2, 2011
  12. Vectors

    Show that if a, b, c are in V3, then (a x b) dot [(bxc)x(cxa]) = [a dot (b x c)]^2 I don't know what properties to use

    asked on February 8, 2011
  13. Physics

    A brass plug is to be placed in a ring made of iron. At 20 degrees Celsius, the diameter of the plug is 8.737 cm and that of the inside of the ring is 8.723 cm. They must both be brought to what common temperature in order to fit? (ANSWER: -210 degrees

    asked on November 16, 2010


    asked on October 3, 2009
  15. Math

    Let xy = 5 and { dy }/{ dt } = 3. Find { dx }/{ dt } when x = 1.

    asked on March 15, 2009
  16. bio

    Hi. i know I already posted this but I don't understand how polyploidy contributes to evolution in finches of the galapagos islands as polyploidy most often occurs in plants.

    asked on January 12, 2009
  17. Math

    The transformation T:R^2--》R^2 is defined by T(1,0)=(2,-5) and T(-3,2)=(1,4). Find the natural matrix of the linear transformation T and find T(x,y).

    asked on December 3, 2017


    asked on May 18, 2013
  19. Physics

    Sphere W (with an initial charge of zero) is touched to sphere A and then they are separated. Next, sphere W is touched to sphere B (with an initial charge of -26e) and then they are separated. Finally, sphere W is touched to sphere C (with an initial

    asked on January 19, 2012
  20. Physics

    A chair with a mass of 30.0kg is shot with a 10g bullet traveling at a speed of 250m/s. The bullet goes 6cm into the chair. The given kinetic friction for for this problem is .2. How far does the chair slide in cm?

    asked on October 2, 2011
  21. Calculus

    Find the equation of the plane through (1,2,-2) that contains the line x = 2t, y = 3 - t, z = 1 +3t

    asked on February 17, 2011
  22. science

    If it happens that a neurotransmitter binds to a receptor site and produces a negative voltage shift, the probability: that the neurons are densely connected decreases. of an excitatory response increases. that the receiving neuron will fire decreases.

    asked on November 8, 2010
  23. Physics

    A sprinter starts from rest in a 100-meter race, accelerates to his full running speed of 10.3 m/s in 1.15 seconds (assume constant acceleration) and continues at that speed for the rest of the race. (a) How far did he run before attaining his full speed?

    asked on September 16, 2010


    asked on October 3, 2009
  25. calculus

    A tank has a rectangular base 3 m × 4 m, the vertical sides are 6 m high, and the depth of the water is 2 m. How much work is required to pump all of the water out over the side? The density of water is 1000 kg/m3 and gravitational acceleration is 9.8

    asked on May 4, 2020
  26. Physics

    You have a neutral balloon. What is its charge after 12000 electrons have been removed from it? The elemental charge is 1.6 × 10−19 C. Answer in units of μC

    asked on February 6, 2018
  27. Mechanical Engineering

    The equation for flow in a circular pipe for a special kind of fluid, called a "power-law" fluid is given by v=(delP/2mL)^1/n * (n/n+1)*[R^(n+1/n) - r^(n+1/n)] where m and n are constants of the fluid, and delP/L is the change in pressure per unit length

    asked on June 29, 2017
  28. please help, Word problem

    At a local baseball game, the concession stand has two different meal choices. you can get 3 hotdogs and 5 drinks for $25.00 or you can get 6 hotdogs and 4 drinks for $29.00. If the price of hotdogs and drinks is the same for each meal, find how much it

    asked on April 11, 2017
  29. Maths

    The angles of elevation of the highest point of a building from two points S and T are 60 degree and 30 degree respectively,T is vertically above S and ST=10m.Calculate the height of the building above the level of S

    asked on February 7, 2017
  30. Algebra

    The number of 37-inch HDTV's that is expected to be sold in a month is double that of 58-inch HDTV's and 50-inch HDTV's combined.sales of 58-inch HDTV's are expected to be equal. 58-inch HD-TV's sell for $4,800, 50-inch HD-TVs sell for $2000, and 37-inch

    asked on June 22, 2015
  31. statistics

    In a class of 100 students, 30 are computer science majors, 49 are mechaincal engineering majors, 13 are civil engineers and the rest are general engineering majors. Assume students only have one major. If a student is chosen at random what is the

    asked on January 16, 2015
  32. math

    Sue has a total of $4000 to invest in two accounts. one account earns 2% simple interest and the other earns 5% simple interest. How much should be invested in both accounts to earn exactly $155 at the end of the year?

    asked on October 3, 2014
  33. algebra

    A plane takes 3 hours to travel 1500 miles with the wind. it can travel only 1380 miles against the wind in the same amount of time. Find the speed of the wind and the speed of the plane in still air.

    asked on October 3, 2014
  34. physics

    A bicycle wheel of radius 0.4 m is spinning at a rate of 40 revolutions per minute. What is the centripetal acceleration of a point on the edge of the wheel? What is the period of the wheel's motion?

    asked on September 28, 2012
  35. physics

    A +50 micro coulomb and 30 micro coulomb charge are placed 50cm apart. a)what is the direction and magnitude of thee electric field at a point P, in between them, that is 10cm from the 30 micro coulomb charge? b)if an electron is placed at rest P, what

    asked on May 3, 2012
  36. Chemistry

    Calculate the heat released from 61.5 g of steam at 111 degrees C is converted to water at 39 degrees C. Assume the specific heat of water is 4.184 J/g*C, the specific heat of steam is 1.99 J/g*C and the enthalpy.H.vap= 40.79 KJ/mol of water

    asked on January 26, 2012
  37. homework

    every yellow marble is -half the orange marbles are -half of all expensive marbles are yellow. there are 40 yellow marbles and 25 expensive marbles that are niether yellow nor orange. how many orange marbles are there?

    asked on October 30, 2011
  38. Physics

    Can someone please help me? The brakes of a truck cause it to slow down by applying a retarding force of 2.60 103 N to the truck over a distance of 930 m. What is the magnitude of the work done by this force on the truck? Is the work positive or negative?

    asked on March 15, 2011
  39. Physics

    Estimate the work you do to mow a lawn 14m by 23m with a 0.5m-wide mower. Assume you push with a force of about 15N.

    asked on September 29, 2010
  40. Physics

    A 1100 kg car is moving toward the north along a straight road at a speed of 20.0 m/s. The driver applies the brakes and the car comes to rest in a distance of 140 m. (a) If the road is completely level, what is the constant force applied to the car to

    asked on September 16, 2010
  41. french

    we have been given a text and have to find words in it. we have to find the word bothers/upsets all i know is that it begins wit 'in' could it be indispose as it is the only word beginning with it we also have to find (here)encounter an it begins with

    asked on November 7, 2009
  42. physics

    show that for a pendulum to oscillate at the same frequency as an object on a spring, the pendulum's length must be L=mg/k thank you

    asked on January 21, 2009
  43. history

    1. The Filipino insurrection led by the Aquinaldo was the result of a. the senate vote ratyfing the treaty of paris ending the spanish american war b. the extension of american military occupation of manila to the entire archipelago 2. The american

    asked on January 19, 2009
  44. Chemistry

    What is the effect on the boiling point of a solution (for example, water) produced by a soluble nonvolatile substance (for example, sodium chloride)? What is the effect of an insoluble substance such as sand or charcoal? I believe if an insoluble

    asked on November 10, 2008
  45. Literary Terms

    What is the difference between Juxtaposition and Antithesis?

    asked on October 27, 2008
  46. Calculus

    Set up a definite integral (but do not evaluate it!) for the area of the surface obtained by rotating the curve y =x^3/3 , 0 ≤ x ≤ 1, about the x-axis. The integral should contain only one variable (x or y).

    asked on May 4, 2020
  47. calculus

    Find the area enclosed by r = θ, and the interval [0, 2π] on the x-axis.

    asked on May 4, 2020
  48. Calculus

    Consider the curve C parametrized by (x, y) = (cos (5t), sin(−4t)), for −π ≤ t ≤ 2pi How would I go about finding how many times the curve is traversed? Also, how would I find out the radius and center of the circle is? I don't need answers I just

    asked on September 9, 2019
  49. math

    How much interest will I owe if I put $10000 on my credit card, with 12% interest, and not pay anything for 4 months?

    asked on September 4, 2019
  50. biology

    Suggest reasons why fats and oils are an efficient form of energy storage for living systems?

    asked on September 26, 2018
  51. Physics

    okay for a) I got the answer as 11.67 seconds and did v=d/t and for b) i found that wavelength= 6km. Im confused how the 100 m deep affects the equation for c and d. The 2011 Japan tsunami was triggered by an earthquake 70 km offshore. The earthquake

    asked on April 18, 2017
  52. Physics

    One more please, I cant figure out the equations. Boats generally have a hard time traveling faster than their hull speed, which is thespeed of a water wave that has the same wavelength as the boat length? (a) What is the hull speed for a 5 meter canoe in

    asked on April 18, 2017
  53. Physics

    You and your friend are talking on a string telephone that is 14 m long. Each of you pulls on the string with about 9 N of force, meaning that the string tension is 9 N. The string has a mass density of 1.2 g/m. How long does it take for your voice to

    asked on April 18, 2017
  54. Physics

    A pipe organ is an aerophone with open ended tubes, with esssentially the same physics as the flute. (a) for normal room temperature, where the speed of sound is about 340 m/s how long is the pipe for the A440 note. (b) Suppose someone wanted to install an

    asked on April 18, 2017
  55. Physics

    You are sitting on a train that is about to drive into a tunnel that is at the base of a large cliff. Just before entering the tunnel, the train blows its whistle, which has a frequency of 600 Hz. (a) What frequency do you hear from the whistle directly?

    asked on April 17, 2017
  56. Physics

    A modern computer central processing unit chip (CPU) runs with a clock speed of 2.7 GHz. It can execute one operation in each of these clock cycles. (a) how many seconds long is one clock cycle? (b) Electrical signals travel at the speed of light How far

    asked on April 6, 2017
  57. science

    What property must a substance have if you want to use the substance to make aqueous solution

    asked on March 21, 2017
  58. Math

    From a point P on the ground which is 100m from the foot of a church tower, the angle if elevation of the top of the tower is 50 degrees calculate the height of the tower...

    asked on September 21, 2016
  59. Physics

    How do you calculate tension

    asked on July 7, 2016
  60. Math-Calc

    Suppose that f(x)=6x(3−2x)3. f(x)=6x(3−2x)3. Find an equation for the tangent line to the graph of ff at x=1x=1.

    asked on May 26, 2016
  61. Physics

    A car drove 17m/s [N] for 10 seconds, and then speeds up to 25m/s [S] for 7.4 seconds. What is the average speed of the car?

    asked on April 24, 2016
  62. Precalculus

    The graph of the parametric equations x=cos(t), y=sin(t) meets the graph of the parametric equations x=2+4cos(s), y=3+4sin(s), at two points. Find the slope of the line between these two points.

    asked on April 9, 2016
  63. Chemistry

    How do you prepare one liter of phosphate buffer 0.01 M at pH 12.0 from 85% phosphoric acid (density 1.69g/ml) and NaOH 1.0 M

    asked on April 7, 2016
  64. math

    simple interest per month on $210,000.00 loan at 1/4% is how much?

    asked on January 17, 2016

    In the following SQL query why do they have an independent letter then period then the table name? I seemed to have missed something in the reading and cannot find it for the life of me SELECT D.DNAME, E.ENAME FROM DEPT D LEFT OUTER JOIN EMP E ON D.DEPTNO

    asked on November 18, 2015
  66. Physics

    An object falls from rest. While falling it changes its speed by 10 meters per second every second. Calculate how far it has fallen, in meters, after falling for 4 seconds. However, do not put the units in the box below.

    asked on November 4, 2015
  67. Physics

    A stone is dropped from the top of a cliff and hits the round below with a speed of 50m/s. Assume that the acceleration due to gravity is 10m/s/s. Find it's mean speed, in m/s, during the fall. Do not include units when typing your answer into the box.

    asked on November 4, 2015
  68. Physics

    A car is initially travelling at 30m/s, which is above the speed limit. The driver sees a speed limit trap ahead and applies the brakes for 5 seconds, causing the car to slow down by 2m/s every second while the brakes are on. How far does the car travel

    asked on November 4, 2015
  69. Physics

    Two blocks with masses m1 = 24.3 kg and m2 = 66.9 kg, shown in the figure, are free to move. The coefficient of static friction between the blocks is 0.34 but the surface beneath m2 is frictionless. What is the minimum force F required to hold m1 against

    asked on October 22, 2015
  70. statics

    5N 30degrees and 10N 45 degrees 10N at 3rd quadrant. find the direction of resultant force.(in degrees) a.)2.74 b.)-4.57 c.)-2.74 d.)5.33 e.)4.57

    asked on August 26, 2015
  71. Area

    How many flowers can you plant in an area 19 square metres if each flower needs 0.04 square metres of space

    asked on August 7, 2015
  72. Algebra problem

    A cyclist travels at an average speed of 12km/h. At this rate how far will he travel in 9h What's the equation for this?

    asked on August 1, 2015
  73. English

    Can you make me a sonnet. 14 lines . 10 syllables. any topic will do.

    asked on July 30, 2015
  74. Computer

    Input Process Output or IPO with Flowchart Question: A reel of electric wire 150 metres long is cut into two pieces.One is 40 metres shorter than twice the length of the other.How long is each piece. Please answer with flowchart.Thanks and god bless.

    asked on July 23, 2015
  75. Math

    A reel of electric wire 150 metres long cut into two pieces. One is 40 metres shorter than twice the length of the other. How long is each piece.

    asked on July 6, 2015
  76. Math

    At an electronics store, the number of 37-inch HGTVs that is expected to be sold in a month is double that of 58-inch HGTVs and 50-inch HGTVs combined. Sales of 58-inch and 50-inch HGTVs are expected to be equal. 58-inch HD-TVs sell for $4800 50-inch

    asked on June 22, 2015
  77. Algebra

    The Jones family bought a new pet rabbit. They want to build an enclosure outside . They have 30ft of lumber. Find the length and width of the enclosure if the length is to be 4ft longer than twice the width.

    asked on June 22, 2015
  78. Algebra

    Oil that costs $22.50/barrel is mixed with oil that costs$35.00/barrel. How many barrels of each oil should be included in 1250 barrels of mixture that sells for $27.50/barrel?

    asked on June 22, 2015
  79. Algebra

    A student has 70%, 80%,79%,and 69% on the first 5 tests . There is one test left and he wants to get at least an 80% in the course. is it possible ? Explain.

    asked on June 22, 2015
  80. algebra

    Deb is slicing up a cake for three people. The cake is 45cm long and the second piece is 10cm longer than the first, and the third piece is 5 cm less than double the first . How big is each slice?

    asked on June 22, 2015
  81. sciences

    Electro magnetic radiations

    asked on May 19, 2015
  82. Chemistry

    How much milk at 10.00°C needs to be added to a small 150.0 ml cup of coffee at 95.00 °C to drop the temperature to 90.00°C? Assume coffee and milk have the same specific heat capacity as water: 4.186 J/g °C or 1 cal/ g °C, and they also have the same

    asked on March 1, 2015

    The demand function for a certain brand of CD is given by p = −0.01x^2 − 0.2x + 12 where p is the unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. The supply function is given by p = 0.01x^2 + 0.7x + 1

    asked on December 3, 2014
  84. math

    A 70% acid solution is to be mixed with a 40% solution. How many gallons of each solutions are needed?

    asked on October 2, 2014
  85. Physics

    Two small pith balls, each of mass m = 17.4 g, are suspended from the ceiling of the physics lab by 1.2 m long fine strings and are not moving. If the angle which each string makes with the vertical is = 17.9°, and the charges on the two balls are equal,

    asked on September 5, 2014
  86. physics

    The top floor of a building is 40m m above the basement. Calculate how much greater the water pressure is in the basement than on the top floor. Express your answer to two significant figures and include the appropriate units.

    asked on April 3, 2014
  87. pyhsics

    The top floor of a building is 40m m above the basement. Calculate how much greater the water pressure is in the basement than on the top floor. Express your answer to two significant figures and include the appropriate units.

    asked on April 3, 2014
  88. physics

    Calculate the average force per nail when Sarah (following figure), who weighs 130 pounds, lies on a bed of nails and is supported by 600 nails. (Figure 1) Express your answer using two significant figures.

    asked on April 3, 2014
  89. physics

    A dike in Holland springs a leak through a hole of area 0.60cm 2 cm^2 at a depth of 1.4m m below the water surface. How much force must a boy apply to the hole with his thumb to stop the leak? Express your answer to two significant figures and include the

    asked on April 3, 2014
  90. physics

    Find its density. Express your answer to two significant figures and include the appropriate units How does this compare with the density of water? Express your answer using two significant figures.

    asked on April 3, 2014
  91. physics

    In the sketch, the small hydraulic piston has a diameter of 2.5cm cm . The large piston has a diameter of 6.4cm cm . For each newton of force applied to the small piston, how many newtons of force are exerted by the large piston? Express your answer using

    asked on April 3, 2014
  92. Statistics

    Compare the standard deviation for the heights of males and the standard deviation for the heights of females in the class.

    asked on March 16, 2014
  93. accounting

    Heww Inc., issued a $50,000, 10 year bond with a stated interest rate of 6%. Assume interest payments are made semi-annually. What is the selling price of the bond if the market rate of interest is 5%? (Round to the nearest dollar.)

    asked on February 13, 2014
  94. Math easy please help

    I just need help with rounding for making sure I round my answer correctly. Can you round this 1.299678785 to the nearest hundredth Thanks :)

    asked on February 10, 2014
  95. Physics 112

    Moving a charge from point A, where the potential is 370V , to point B, where the potential is 190V , takes 4.1×10−4J of work. Part A What is the value of the charge?

    asked on January 30, 2014
  96. physics

    solid sphere of uniform density starts from rest and rolls without slipping down an inclined plane with angle è = 30o. The sphere has mass M = 8 kg and radius R = 0.19 m . The coefficient of static friction between the sphere and the plane is ì = 0.64.

    asked on March 31, 2013
  97. Algebra

    A rectangle is 5 times longer then it is wide. If perimeter of the rectangle is 222m. What are its dimensions

    asked on March 27, 2013
  98. math

    Phil invested $150 at an annual rate of 4% compounded continuously, what amout to the nearest cent will be in his account after 2 years? Graph the amount in his account over the first 8 years.

    asked on February 20, 2013
  99. math

    A cable company charges $40 plus $12 for each cable jack. If x is the number of jacks installed, the linear equation is C=12x+40. graph the total

    asked on February 20, 2013
  100. Physics

    A small object of mass 2.60 g and charge -17 µC "floats" in a uniform electric field. What is the magnitude and direction of the electric field?

    asked on February 17, 2013


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