# how much heat is required to melt an ice cube that is 4.2 cm x 2.1 cm x 2.9 cm? The density of ice is 0.92 g/cm3

22,259 questions, page 176
1. ## physics

A stunt man whose mass is 70 kg swings from the end of a 4.4 m long rope along the arc of a vertical circle. Assuming that he starts from rest when the rope is horizontal, find the tensions in the rope that are required to make him follow his circular path

asked by Cho on November 6, 2010
2. ## physics

You are riding a carousel that is turning at a constant angular velocity. You must pull toward the center with 100N of force to stay in place. You decide to move radially toward the center of the carousel to ride on a small animal figure that is at half

asked by Girma on September 23, 2014
3. ## physics

A dockworker loading crates on a ship finds that a 21-kg crate, initially at rest on a horizontal surface, requires a 70-N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 51 N is required to keep it moving

asked by monic on October 2, 2012
4. ## CHEMISTRY

A 2.800-g mineral sample was analyzed for its calcium carbonate, CaCO3, content by titrating it with hydrochloric acid (the reaction products are calcium chloride, carbon dioxide, and water). The sample required 28.48 mL of a 0.1505 M HCl solution to react

asked by Anonymous on November 28, 2010
5. ## physics

A dockworker loading crates on a ship finds that a 21-kg crate, initially at rest on a horizontal surface, requires a 70-N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 51 N is required to keep it moving

asked by Anonymous on September 30, 2012
6. ## Physics

A dock worker loading crates on a ship ﬁnds that a 18 kg crate, initially at rest on a horizontal surface, requires a 71 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 46 N is required to keep it

asked by Aaron on March 21, 2013
7. ## physic =)

A bullet is fired directly upward from a rifle at ground level. Assuming a velocity muzzle of 490 m/s, and neglecting air resistance, find: A.height of the highest point reached. B.time required to reach this point. C.total time before the bullet returns

asked by carol on January 6, 2013
8. ## chem 12

consider the following equilibrium 2NOCl(g)--- 2 NO(g) + Cl2(g) Initally 1.00 mol of NO and 1.00 mol of Cl2 are placed in a 5.00L container. Calculate the initial concentrations of NOCl, NO and Cl2 NO= 0.20 mol/L Cl2= 0.20 mol/l NOCl=0 At equilibrium it is

asked by George on March 8, 2016
9. ## CHEMISTRY HELP!!

Formic acid (HCHO2) is a component of bee stings. It is a weak acid and dissociates according to the equilibrium shown below: HCHO2 H+ + CHO2- Kc = 1.8 x 10-4 For a 0.5 M solution of formic acid, we wish to determine the equilibrium concentration of H+.

asked by carlo on April 28, 2011
10. ## Water - Math Question

This question is related to water footprint calculation. I have no idea how to go about this, if anyone could point me in the right direction, I'd be forever grateful! Background info: The water footprint of the resident of a Blue Sea riparian country (92

asked by Allison on October 19, 2013
11. ## Damon check step by step

25g of a sample of ferrous sulphate was dissolved in water containing dilute h2s04 and the volume made up to one litre. 25ml of this solution required 20ml of N/10 kmn04 solution for complete oxidation. Calculate the percentage of f2s047h20 in the sample

asked by Fai on January 2, 2014
12. ## economics

As such, you are assigned the duty of ensuring the availability of 100,000 yen for a payment scheduled for next month. Considering that your company possesses only US dollars, identify the spot and forward exchange rates. What are the factors that

asked by Anonymous on February 21, 2010
13. ## Basic Word and Excel

What would be a situation in which you could use an Excel chart to present your data? a.)determining what percentage of customer 101 buys product A, and what percentage of the same customer buys product B b)Compiling survey questions and answers from both

asked by Lee on December 5, 2017
14. ## Physics

A marble rolls down an incline of 30 degrees. If the marble is initally at rest at the top of the incline of length 2.0 meters what will the speed of the marble be at the bottom of the incline (a) if the incline is rough enough to prevent any slipping [ it

asked by Anonymous on November 21, 2014
15. ## Chemistry/Math

I went to my teacher numerous times. I'm still not using the right formulas or equations. Please help. A commonly used rule of thumb is that average velocity in a pipe should be about 1 m/s or less for "thin" (viscosity about water). If a pipe needs to

asked by Angie on September 4, 2012
16. ## AP Physics

An airplane in a horizontal circle at a speed of 130.5556 m/s. If its wings are tilted 40 degress to the horizontal, what is the radius of the circle in which the plane is flying? Assume that the required force is provided entirely by an "aerodynamic lift"

asked by Kristen on October 28, 2007
17. ## Chemistry

25ml of sulfuric acid from a car battery was accurately diluted to 500ml. 25ml of the diluted solution was titrated with 0.206 mol/L sodium hydroxide. It required 38.8 ml. Calculate the Molarity of the original battery acid and it's concentration in grams

asked by Jo on March 11, 2018
18. ## Ap Chemistry

at 25 degrees Cliquid A has a vapor pressure of 100.0 torr, while liquid B has a vapor pressure of 200.0 torr. The heat of vaporization of liquid A is 32.0 kJ/mol and that of liquid b is 18.0 kJ/mol. At what celsius temperature will A and B have the same

asked by John on January 23, 2008
19. ## Chemistry

Gasoline is a mixture of hydrocarbons, a major component of which is octane,CH3CH2CH2CH2CH2CH2CH2CH3. Octane has a vapor pressure of 13.95 torr at 25 degrees celcius and a vapor pressure of 144.78 torr at 75 degrees celcius. Use these data and the equation

asked by Jeremy on January 25, 2012
20. ## Physical Science

The sand on the beach heats up faster each day than the water does. You know this because when you walk on the beach in the early morning, your feet are cool. By noon, the beach is so hot, you cannot walk on it in bare feet . The ocean, however stays cool.

asked by Bonni on October 20, 2014
21. ## Physics

How much energy does it extract from the outside air with coefficient of performance 3.85? A heat pump has a coefficient of performance of 3.85 and operates with a power consumption of 6.91 x 10^3 W. The first part of the question asked How much energy

asked by Z32 on February 16, 2011
22. ## Chemistry

Constant-volume calorimeters are sometimes calibrated by running a combustion reaction of known ΔE and measuring the change in temperature. For example, the combustion energy of glucose is 15.57 kJ/g. When a 2.500 g sample of glucose burns in a constant

asked by Kales on October 23, 2014
23. ## PHYSICS

At a nuclear power plant water at 8°c from a lake is used in a heat exchanger to condense spent steam at a temperature of 120°c,to water at 85°c before it is recycled to the reactor. If the cooling water returns to the lake at a temperature of 19°c,how

asked by Riana on March 31, 2013
24. ## physics

At a nuclear power plant water at 8°c from a lake is used in a heat exchanger to condense spent steam at a temperature of 120°c,to water at 85°c before it is recycled to the reactor. If the cooling water returns to the lake at a temperature of 19°c,how

asked by Riana on March 31, 2013

At a nuclear power plant water at 8°c from a lake is used in a heat exchanger to condense spent steam at a temperature of 120°c,to water at 85°c before it is recycled to the reactor. If the cooling water returns to the lake at a temperature of 19°c,how

asked by Riana on March 31, 2013
26. ## physics

At a nuclear power plant water at 8°c from a lake is used in a heat exchanger to condense spent steam at a temperature of 120°c,to water at 85°c before it is recycled to the reactor. If the cooling water returns to the lake at a temperature of 19°c,how

asked by Riana on March 31, 2013
27. ## Chemistry Last

Last question: An average person expends ~100 kj to walk 1km. How far will the average car travel by the time it expends the same amount of energy (i.e. 100 kJ) as a person who walked 1 km? Fuel consumption of average car= 8 km L^(-1) Heat of combustion of

asked by Amy~ on August 29, 2010
28. ## science

I guess I'm missing something here...but I've approached this question in every possible angle and im just not getting it! Could somebody point me in the right direction? Here is the question: If the measured net radiation (Q*) for the lawn of your home in

asked by Kathleen on October 1, 2009
29. ## physics

A dock worker loading crates on a ship finds that a 25 kg crate, initially at rest on a hori- zontal surface, requires a 90 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 51 N is required to keep it

asked by Sara on March 14, 2011
30. ## MATH

1. Jacob mixes the letters J, K, L, J, K, M, N, and P thoroughly. Without looking, Terry draws one letter. Expressed as a fraction, decimal, and percentage, what is the probability that K will not be the letter Terry selects? (1 point) one-fourth, 0.25,

asked by Anonymous on March 9, 2017
31. ## Thermodynamics

a rigid vessel of volume 1m(^3) contains steam at 20bar and 400 degrees Celcius. The vessel is cooled until the steam is just dry saturated. Calculate the mass of steam in the vessel, the final pressure of the steam and the heat rejected during the

asked by Claire on March 12, 2010
32. ## chemistry

2.) If you pass 10.0mL of a 50.0mL solution of [Co(en)2Cl2]Cl that has been reduced with Zn through a cation exchange column, you will obtain a solution that has three H+ ions for every Co3+ ion that was originally present in the sample. These H+ ions are

asked by xx on October 26, 2014
33. ## poetry (Pioneer by Dorothy Livesay)

I have to answer the questions according to this poem, I have answered them but just want someone to look over them to see if they are right. The last one I had trouble with and need help on that one too. The answer that I think it is I have put arrows on

asked by Gary on October 7, 2013
34. ## Physics

Hockey puck A initially travels at  v(initial) = 6.2 m/s in the horizontal direction (East) on a smooth horizontal ice before striking hockey puck B which is initially at rest, off-center.  After the collision, A is deflected at Î¸ =  23 degrees

asked by AH on October 25, 2012
35. ## chemistry

Energy must be transferred into or out of a system in order to cause phase change.In addition changes in the energy can be directly related to pressure volume changes.If equal moles of each gas is compressed which one would have the largest pressure volume

asked by treasa on October 21, 2017
36. ## chemistry

In a methane fuel cell, the chemical energy of the methane is converted into electrical energy instead of heat that would flow during the combustion of methane. Using the half-reactions and reduction potentials given below a) Write a net equation for the

asked by Vt on August 3, 2011
37. ## chemistry

In a methane fuel cell, the chemical energy of the methane is converted into electrical energy instead of heat that would flow during the combustion of methane. Using the half-reactions and reduction potentials given below a) Write a net equation for the

asked by Vt on August 3, 2011
38. ## chemistry

Energy must be transferred into or out of a system in order to cause phase change.In addition changes in the energy can be directly related to pressure volume changes.If equal moles of each gas is compressed which one would have the largest pressure volume

asked by treasa on October 21, 2017
39. ## chemistry

Energy must be transferred into or out of a system in order to cause phase change.In addition changes in the energy can be directly related to pressure volume changes.If equal moles of each gas is compressed which one would have the largest pressure volume

asked by treasa on October 21, 2017
40. ## q, w, and DU

A gas is allowed to expand at constant temperature from a volume of 2.00 L to 11.20 L against an external pressure of 1.500 atm. If the gas loses 256 J of heat to the surroundings, what are the values of q, w, and DU? Pay careful attention to units. a.

asked by Raymonddd on June 12, 2009
41. ## Physics

An ideal gas in a moveable piston is allowed to reversibly expand by slowly heating at constant pressure. a. Derive the equation for the work done reversibly as a function of the initial and final temperatures.( i have used w=-nrtln(v final/v intial) i

asked by Carlos on February 28, 2017
42. ## Chemistry

Nickel (Ni) is an element found in Group 10 of the periodic table of elements (see periodic table at the top of this quiz). Based on its location in the periodic table, which of these is a property of nickel? A Low density B Strong semi conductor C Highly

asked by Elite on March 1, 2017

What is the molar solubility of barium phosphate in a 0.282M barium acetate solution? If I set up and ice table I would have 0.282M - X = ? Would I use the molar mass of barium acetate to complete the equation to find X? Ba3(PO4)2 ==> 3Ba^2+ + 2PO4^3-

asked by Hannah on April 28, 2012
44. ## CHEMISTRY

You carry out a reaction with 28.9mL of 0.711M solution of NiNO3)2. The reaction has a change in H of -26.4KJ/mol rxn. What is the q, the heat of the reaction, in joules? I first found the mols of the solution using molarity and then found the joules of

asked by markymark on April 23, 2013
45. ## chemistry

a 225.0g sample of an unknown, silver, pure metal was heated to 95.5 degrees Celsius and then put into 150.50g of water at 22.5 degree Celsius. the water was heated by the hot metal to a temp. of 31.4 degree Celsius. what is the specific heat of the metal

asked by brittany on March 15, 2013
46. ## AP Chem

The heat of combustion of octane (C8H18) is 47.8 kJ/g and one gallon of C8H18 has a mass of 2620 g. If a car using octane is driven 10,000 miles in one year and gets 25 miles per gallon of octane, what is the total energy consumption? 1. 5.01 × 107 kJ 2.

asked by Kai on November 14, 2010
47. ## Chem

The heat of combustion of octane (C8H18) is 47.8 kJ/g and one gallon of C8H18 has a mass of 2620 g. If a car using octane is driven 10,000 miles in one year and gets 25 miles per gallon of octane, what is the total energy consumption? 1. 5.01 × 107 kJ 2.

asked by Kai on November 14, 2010
48. ## Physics

Two equal-mass stars orbit their centre of mass. The distance between the stars (measured from the centre of mass of each) is 1 AU. What is the period of revolution in years? How much energy would be required to unbind these stars if they each have the

asked by Jim on August 14, 2015
49. ## MATH

FIND A AREA OF SQUARE ROOM WHOSE SIDE IS 6CM. THE FLOOR OF ROOM IS TO BE TILLED WITH SQUARE TILES HAVING A SIDE OF 60CM.FIND THE NO.OF TILES REQUIRED

asked by SAKSHI on March 4, 2013
50. ## Trig

a. Find the magnitude of the force required to keep a 3100​-pound car from sliding down a hill inclined at 5.7° from the horizontal. b. Find the magnitude of the force of the car against the hill.

asked by Erin on July 14, 2018
51. ## Chemistry

The bad smell of water containing hydrogen sulfide can be removed by the action of chlorine. The reaction is H2S(aq) + Cl2(aq)-->2HCl(aq) + S(s) If the hydrogen sulfide content of contaminated water is 22 ppm by mass, calculate the amount of Cl2 (in grams)

asked by sokun on March 11, 2011
52. ## Algebra

Gloria has a gallon of paint to cover 500 square feet of drywall. She pointed out that for 10,000 square feet she needs 20 gallons of paint. Let's say the output (the range) is going to tell us how many gallons of paint to buy at the hardware store. The

53. ## English

After reading cat's eye by margaret Atwood, I had to write a essay. the essay required me to write an analytical essay detailing 3 events in the story where Atwood notably develops specific character traits in elaine Risley so that the reader can Identify

asked by Carly on August 24, 2012
54. ## Algebra

Gloria has a gallon of paint to cover 500 square feet of drywall. She pointed out that for 10,000 square feet she needs 20 gallons of paint. Let's say the output (the range) is going to tell us how many gallons of paint to buy at the hardware store. The

55. ## Chemistry

A sample of 0.314g of unknown monoprotic weak acid, HA was dissolved in 25.00 mL of water and titrated with 0.1M KOH. The acid required 27.20 mL of the base to reach equilibrium point. Find the pH of the solution if 40 mL KOH is added to the acid solution.

asked by Lee on October 25, 2018

A force of 23.0 N is required to start a 3.0 kg box moving across a horizontal concrete floor. (a) What is the coefficient of static friction between the box and the floor? 1 (b) If the 23.0 N force continues, the box accelerates at 0.50 m/s2. What is the

asked by Cameron on November 14, 2010
57. ## Managerial accounting

well, I am doing direct material budget, and already have my production budget. for example for the quarter, for January I get 950, and cost for Direct material it says to be \$8/unit, but it does not say the units need for production, so im confused.

asked by Mike on April 22, 2015
58. ## Physics

A force of 40 N is required to start a 5 kg box moving across a horizontal concrete floor. (a) What is the coefficient of static friction between the box and the floor? (b) If the 40 N force continues, the box accelerates at 0.70 m/s2. What is the

asked by Harry on December 4, 2012
59. ## Chemistry

A calorimeter contains 50.0 mL of water; both are at 21.2 degrees C. Then the 50.0 mL of water at 57.6 degrees C is added to the calorimeter. At equilibrium, the final temperature of the water and the calorimeter is 33.3 degrees C. Calculate the heat

asked by Jay on October 22, 2013
60. ## Chemistry

Hydrogen peroxide, H2O2, solution can be purchased in drug stores and used as an antiseptic. A sample of such a solution weighing 1.00 grams was acidified with sulfuric acid and titrated with .02000 M solution of KMnO4. The unbalanced reaction is H2O2(aq)

asked by HELP!!! on April 15, 2010
61. ## physics

Each of the four wheels of the vehicle weighs 40 lb and is mounted on a 4in diameter journal. The total weight of the vehicle is 960 lb, including wheels, and is distributed equally on all four wheels. If a force P = 16 lb is required to keep the vehicle

asked by Jessi on September 13, 2009
62. ## Math

My class was awarded \$30.000.00 for winning a Spelling Bee competition and my classmates have agreed to use the money towards a class activity.Suggestions were: (a)An educational tour (b)A class party I am required to : (a) carry out a survey to determine

asked by Oxsana on March 10, 2009
63. ## Chemistry

The following information is given for ethanol, C2H5OH, at 1atm: boiling point = 78.4oC Hvap(78.4oC) = 38.6 kJ/mol melting point = -115oC Hfus(-115oC) = 5.02 kJ/mol specific heat liquid = 2.46 J/goC At a pressure of 1 atm, what is H in kJ for the process

asked by Jordan on January 24, 2011
64. ## Chemistry

Baking soda is sodium bicarbonate (NaHCO3). When you heat baking soda, it breaks down into sodium carbonate powder (Na2CO3), water vapor, and carbon dioxide. The enthalpy of this reaction is 129 kJ. Write a correct thermochemical equation for this

asked by student on April 18, 2019
65. ## Exploring Space

if a satellite were to be launched with too little speed or too much speed then what would happen? If a sattellite were to be launched with too much speed then the friction in the air would make it heat up to the point where it would burn up. Earth's

asked by Sara on March 15, 2010
66. ## chemistry

2. Baking soda is sodium bicarbonate (NaHCO3). When you heat baking soda, it breaks down into sodium carbonate powder (Na2CO3), water vapor, and carbon dioxide. The enthalpy of this reaction is 129 kJ. Write a correct thermochemical equation for this

asked by dd on May 14, 2012
67. ## Psychology-24Hour Cycle

Our tendency to feel wakeful and sleepy on a 24-hour basis depends mainly on a. a cycle generated by a mechanism in the brain b. our perception of environmental stimuli such as heat and light c. a cycle generated by hormone-producing organs such as the

asked by Melissa on October 18, 2007
68. ## sci

a radiator is attached to a wall on one side of a room. which is mostlikely way its heat will warm the air on the other side of the room? a. by conduction b. by convection c. the warm air will sink and condense d. the warm air will rise and condense

asked by somebody help i am new on December 1, 2014
69. ## Physical Science

You submerge 100 grams of steel in 200 grams of water. If the steel has an initial temperature of 80°C and the water has an initial temperature of 10°C, what is the final temperature of the system? The specific heat capacity of the steel is 0.15

asked by Connor on October 12, 2012
70. ## physics

an engine block of mass 275kg rest on a plane which is inclined at 13 degrees to the horizontal.if the plane can be tilted to a maximum angle of 21 degrees before the engine block slide due to its weight.calculate the minimum force parallel to the plane

asked by charles on October 6, 2010
71. ## General Chemistry

So I've been working on this online homework problem and got it wrong 8 times. I need help. Here's the question: 1,2-diaminoethane, H2N-CH2-CH2-NH2, is used extensively in the synthesis of compounds containing transition-metal complexes in water. If pK_b1

asked by Dre on July 25, 2011
72. ## English

Thank you for suggesting me a website on audiobooks. Here are some sentences I'm not sure of. 1) Dr. Frankenstein can be seen as Rousseau's primitive man, detached from society and unspoilt by civilization. 2)He can also be seen as the dark side of

asked by Franco on December 30, 2010
73. ## physics

contains 200 grams of oil that's 30 degrees celsius they add 100 grams of that oil that's 70 degrees celsius the balance temperature is 40 degrees celsius what's the specific heat capacity of the oil

asked by Anonymous on May 15, 2011
74. ## Physics

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 40 degrees celcius?

asked by Hunter on January 29, 2012
75. ## Physics

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 49 degrees celcius?

asked by Hunter on January 29, 2012
76. ## Physics

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 49 degrees celcius?

asked by Hunter on January 29, 2012
77. ## Physics

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 49 degrees celcius?

78. ## PHYSICS

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 49 degrees celcius?

asked by Hunter on January 29, 2012
79. ## Physics

You have 300 g of coffee at 55 degrees celcius. Coffee has the same specific heat as water. How much 10 degrees celcius water do you need to add in order to reduce the coffee's temperature to a more bearable 49 degrees celcius?

80. ## Language/Listening Skills

Which activity would be the least likely to encourage listening skills? A.) Mr. Greer told his students about the first time he rode a bicycle. He asked Eric to tell him about his first time on a bike. B.) Mr. Greer told the children that his favorite kind

asked by Shannon Beth on September 6, 2007
81. ## physics

A dock worker loading crates on a ship ﬁnds that a 29 kg crate, initially at rest on a horizontal surface, requires a 90 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 60 N is required to keep it

asked by sam on December 3, 2013
82. ## physics

A dock worker loading crates on a ship ﬁnds that a 29 kg crate, initially at rest on a horizontal surface, requires a 90 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 60 N is required to keep it

asked by sam on December 3, 2013
83. ## econ

Consider a change in the table in Problem 2-3. The student’s set of opportunities is now as follows: Economics Biology 100 40 90 60 80 75 70 85 60 93 50 98 40 100 Plot this student’s production possibilities curve. Does the PPC illustrate increasing or

asked by rayne on September 14, 2011
84. ## Chemistry

When 22.7mL of o.500 M H2SO4 is added to 22.7mL of 1.00 M KOH in a coffee-cup calorimeter at 23.50 degrees Celsius, the temperature rises to 30.17 degrees Celsius. Calculate the delta h of this reaction. (Assume that the total volume is the sum of

asked by Sean on October 19, 2012
85. ## Science- physics

An iron anchor weighs 250 pounds in air and has a weight density of 480 lbs/ft3. If it is immersed in sea water that has a weight density of 64 lbs/ft3, how much force would be required to lift it while immersed? I know the answer is 217 pounds but I need

asked by Hannah on October 23, 2011
86. ## Physics

Rubber Band A 156 g hockey puck is attached to a rubber band and rotated with an angular speed of 9.8 rad/s on frictionless horizontal ice. It takes a force of 1.12 N to stretch the rubber band by 1 cm. (a) If the original length L of the rubber band is 1

asked by Help on December 3, 2010
87. ## Chemistry

20.7mL of ethanol (density=0.789g/mL) initially at 8.2 degrees Celsius is mixed with 37.1 mL of water (density=1.0g/mL) initially at 25.7 degrees Celsius in an insulated beaker. Assuming that no heat is lost, what is the final temperature of the mixture?

asked by Katie on February 7, 2012
88. ## physics

A 2000-kg automobile with four-wheel drive and weight distributed equally on the four 60-cm diameter wheels can accelerate from 0 to 27 m/s (60 MPH) in 6 seconds. a. Calculate the minimum coefficient of static friction between the tires and the ground. (10

asked by jennifer on December 4, 2016
89. ## Math

An airline runs a commuter flight between Portland and Seattle, which are 145 miles apart. If the average air speed could be increased by 40 miles per hour, the travel time would be decreased by 12 minutes. What air speed is required to obtain this

asked by Amy on November 2, 2011
90. ## Physics

At what rate must a cylindrical spaceship rotate if occupants ar to experience simulated gravity of 1/2g? Assume the spaceship's diameter is 32 m, and give your answer as the time needed for one revolution. The centripetal acceleration is R w^2, where R is

asked by Sam on January 2, 2007
91. ## Math

For an experiment on the titration of a supernatant liquid I need to calculate the number of moles of S2O3^2-^ ion required using the volume of SrIO3 solution(supernatant liquid) from the two trials that were conducted. For both trials the volume of SrIO3

asked by Hannah on April 9, 2012
92. ## Physics

A car which has a mass of 1.36 tonnes is travelling at 26.8m/s on a level road when the driver brings the car to an emergency stop using only the brakes. A time interval of 4.18s is required to bring the car to a stop. 1. Calculate the position of the car

asked by Anonymous on October 16, 2018
93. ## American History

Based on the information on the map, what can you infer about industry in the United States? A. Manufacturing was a key part of the economy in the Northeast*** B. Agriculture was the main industry in the south C. Mills in the Northeast had to be close to

asked by Lol on February 21, 2018
94. ## chemistry

The formula for epsom salt is MgSO4 . 7H20 If 1.250 g of the compound is dissolved in water, calculate the number of milliliters of .200 M Ba(NO3)2 that would be required to precipitate all of the sulfate ions as barium sulfate. I got that right with an

asked by kelly on October 10, 2010
95. ## Physics

Calculate the specific heat capacity of substance x from the following data. A container made of the substance x has a mass of 3.6kg and contains 14kg of water. A 1.8kg-piece of the substance x initially at the temperature of 180°C is dropped into the

asked by Francis on November 20, 2017
96. ## Physics

The efficiency of a pulley system is 47 percent. The pulleys are used to raise a mass of 47 kg to a height of 7.0 m. The acceleration of gravity is 9.81 m/s 2 . What force is exerted on the rope of the pulley system if the rope is pulled for 28 m in order

97. ## algebra

A flagpole has a height of 6565 yards. It will be supported by three​ cables, each of which is attached to the flagpole at a point 55 yards below the top of the pole and attached to the ground at a point that is 3232 yards from the base of the pole. Find

asked by melissa on April 10, 2016
98. ## help!

How are physical characteristics combined with behavioral characteristics by northern mammals to conserve heat during extreme periods? http://en.wikipedia.org/wiki/Hibernation http://en.wikipedia.org/wiki/Estivation In addition to the excellent information

asked by help! on August 12, 2006
99. ## Science- Chemistry

How do I figure these out? A solution of sodium thiosulfate, Na2S2O3, is 0.1365 M. 29.28 mL of this solution reacts with 39.79 mL of I2 solution. What is the molarity of the I2 solution? 2(Na2S2O3) + I2↔Na2S4O6 + 2(NaI) 16.77 mL of the I2 solution from

asked by Whitney on November 8, 2012
100. ## science

a car of mass 100 kg traveling at 72 km/hr is brought to rest by applying the brakes.assuming that the kinetic energy of the car becomes transferred to internal energy in four steel brakes drum of equal mass, fine the rise in temperature of the drums if

asked by ing-marie on May 8, 2013