# Stuck

Most popular questions and responses by Stuck-
## Physics

A jet plane traveling 1890 km/h (525 m/s ) pulls out of a dive by moving in an arc of radius 5.20 km What is the plane's acceleration in g's?

*asked on November 9, 2016* -
## Calculus - another question

"The side of an equilateral triangle decreases at the rate of 2 cm/s. At what rate is the area decreasing when the area is 100 cm^2?" Help!

*asked on March 9, 2010* -
## Chemistry/Physics

"Colbalt-60 is a radioactive isotope used to treat cancers of the brain and other tissues. A gamma ray emitted by an atom of this isotope has an energy of 1.33 MeV (million electron volts; 1 eV = 1.602*10^-19 J). What is the frequency (in Hz) and

*asked on March 10, 2010* -
## Physics

"A fish hangs from a spring scale supported from the roof of an elevator. If the elevator has an upward acceleration of 1.2m/s^2 and the scale reads 200N, under what circumstances will the scale read 150N? What will the scale read if the elevator cable

*asked on July 12, 2010* -
## Calculus

"At 9am ship A is 50 km east of ship B. Ship A is sailing north at 40km/h and ship B is sailing south at 30km/h. How fast is the distance between them changing at noon?" I can never get these type of questions where two ships are heading in different

*asked on June 17, 2010* -
## chemistry

Calculate the value of q for each of the experiments listed below. (Assume the heat capacity of water is 4.1801 J/g*C). Exp1: 2.48g of an unknown salt added to 160. mL of water resulted in a change of temperature of -0.1 C. Exp2: 2.48g of an unknown salt

*asked on July 7, 2014* -
## Physics

"An airplane is climbing at an angle of 15 degrees to the horizontal with the sun directly overhead. The shadow of the airplane is observed to be moving across the ground at 200 km/h. How long does it take for the plane to increase its altitude by 1000 m"?

*asked on July 6, 2010* -
## Physics

"A diver springs upward with an initial speed of 1.8 m/s from a 3.0 m board. Find the velocity with which the diver strikes the water." Help please!

*asked on July 5, 2010* -
## Physics

Calculate the force of earths Gravity on a 2.00 earth radii above the earth surface if it's mass is 1850kg.

*asked on November 6, 2016* -
## Calculus - another question

"Margaret has found that by a proper choice of gears she can steadily increase her speed on her bike. One day she sets out and, ten minutes later, she achieves her cruising speed of 30km/h by increasing her speed steadily. How far did she travel in that

*asked on April 1, 2010* -
## Physics

"An athlete whirls a 3.7kg shot-put in a horizontal circle with a radius of 0.90m. If the period of rotation is 0.30s, how far would the shot-put travel horizontally if it is released 1.2m above the level ground?" There were two other parts to the question

*asked on July 14, 2010* -
## Chemistry

"Given that the bond enthalpy of the carbon-oxygen bonds in carbon monoxide and carbon dioxide are 1073 kJ/mol and 743 kJ/mol respectively, and that of the bond in the oxygen molecule is 496 kJ/mol, calculate the enthalpy change for the combustion of 1

*asked on April 8, 2010* -
## Physics

"A roller coaster reaches the top of the steepest hill with a speed of 1.4m/s. It then descends the hill which is at an average angle of 45 degrees and is 50m long. What will its speed be when it reaches the bottom?"

*asked on July 12, 2010* -
## Chemistry

"For which of the following equations is the value of delta H equivalent to the bond enthalpy for the carbon-oxygen bond in carbon monoxide? A. CO(g)-> C(g) + O(g) B. CO(g)-> C(s) + O(g) C. CO(g)-> C(s) + 1/2 O2(g) d. CO(g)-> C(g) + 1/2 O2 (g)" I'm

*asked on April 7, 2010* -
## Physics

"Water flows over a section of Niagara Falls at the rate of 1.2*10^6 kg/s and falls 50.0m. How much power is generated by the falling water?" It's a the kg/s that is confusing me. I don't know how to work with it.

*asked on July 25, 2010* -
## Calculus

"The illumination of an object by a light source is directly proportional to the strength of the source and inversely proportional to the square of the distance from the source. Two streetlights are 40m apart and one is twice as strong as the other. Where

*asked on June 20, 2010* -
## physics

The speed of sound in air is approximately 340 m/s. The speed of sound in steel is approximately 5900 m/s. If your friend strikes one end of a steel pipe with a hammer while you listen at the other end, you will hear two distinct sounds: one traveling

*asked on October 12, 2016* -
## Physics

Does an apple exert a gravitational force on the earth? If so, how large a force? Consider an apple (a) Attached to a tree and (b) falling.

*asked on November 6, 2016* -
## Chemistry

"Find the total energy lost by the contents of a Styrofoam picnic cooler when a 3.60 kg block of ice placed inside the cooler completely melts (at 0 Celsius). The ice had an initial temperature of -10.00 Celsius." (Answer is 1.27*10^3 kJ). I was thinking

*asked on February 12, 2010* -
## Physics - Another Question

"Three forces act at a single point. Two of the forces are 39N southwest and 45N north. What is the value of the third force that creates equilibrium?"

*asked on July 28, 2010* -
## Math

"A tank holds 1000L of water, which takes an hour to drain from the bottom of the tank, then the volume V of water remaining in the tank after t minutes is: V = 1000(1-(t/60))^2 where t is between 0 and 60 inclusive. Find the rate at which the water is

*asked on February 7, 2010* -
## Physics

"Two springs are hooked together and one end is attached to a ceiling. Spring A has a spring constant of 25N/m, and spring B has a spring constant of 60N/m. A mass weighing 40.0N is attached to the free end of the spring system to pull it downward from the

*asked on July 19, 2010* -
## Physics - Another Question

"Two girls, one of mass 40kg and the other of mass 60kg, are standing side by side in the middle of a frozen pond. One pushes the other with a force of 360N for 0.10s. The ice is essentially frictionless. What is each girl's acceleration?"

*asked on July 12, 2010* -
## Physics

"A workman sitting on top of a roof of a house drops his hammer. The roof is smooth and slopes at an angle of 30.0 degrees to the horizon. It is 32m long and its lowest point is 32m from the ground. How far from the house's wall is the hammer when it hits

*asked on July 29, 2010* -
## Physics

"Two wooden blocks A and B have respective masses of 3.0kg and 4.0kg and are connected with an inextensible cord. If the blocks are placed on a horizontal frictionless surface and a force of 8.0N is applied to A, find the tension in the connecting cord."

*asked on July 28, 2010* -
## Calculus

"At 9am ship A is 50 km east of ship B. Ship A is sailing north at 40km/h and ship B is sailing south at 30km/h. How fast is the distance between them changing at noon?" I never know how to set questions like this up!

*asked on June 16, 2010* -
## AP physics

Astronauts who spend long periods in outer space could be adversely affected by weightlessness. One way to stimulate gravity is to shape the spaceship like a cylindrical shell that walking on the inside surface. Explain how this simulates gravity. Consider

*asked on November 6, 2016* -
## Chemistry

"Energy is released when 100 kg of steam at 150 degrees Celsius and standard pressure changes to water at 60 degrees Celsius. Calculate the total energy change". I used q=mct to find the energy required to change to 100 degrees Celsius. But now what??

*asked on February 17, 2010* -
## Physics

"A mass of 3.08kg oscillates on the end of a horizontal spring with a period of 0.323s. What acceleration does the mass experience when its displacement is 2.85m to the right?"

*asked on July 26, 2010* -
## Math

"The probability of getting heads on a biased coin is 1/3. Sammy tosses the coin 3 times. Find the probability of getting two heads and one tail". I thought that all you have to do is: (1/3)(1/3)(2/3) It makes sense to me, but it's not right...

*asked on May 3, 2010* -
## Statistics/Probability

Bottles of water are labeled as containing 12 oz. Statistics students weighted the content of 7 randomly chosen bottles and found the mean weight to be 12.15 oz. Assume that bottles of water are filled so that the actual amounts are normally distributed

*asked on July 11, 2009* -
## Math

"Three of the coordinates of the parallelogram STUV are S(-2,-2), T(7,7) and U(5,15). State the vector ST and hence determine the coordinates of V." So I've figured out that ST = (9,9), but I don't see how that helps me find V.

*asked on May 5, 2010* -
## Intermediate Algebra

A basketball team recently scored a total of 95 points on a combination of 2-point field goals, 3-point field goals, and 1-point foul shots. Altogether, the team made 54 baskets and 16 more 2-pointers than foul shots. How many shots of each kind were made?

*asked on February 20, 2014* -
## Physics

"If a small planet were located 8 times as far as the Earth's distance from the Sun, what would be its period in Earth years?" (22.5 earth years) As a note, we are given a table with all of the planets' masses and radii.

*asked on July 15, 2010* -
## Physics

"An object is rolled up an incline. If the object is 2.75 m up the incline after 4.50s and rolling back down at a velocity of 1.90 m/s, what is the acceleration of the object?" Is this a case of final velocity - initial velocity?? It seems like an easy

*asked on July 5, 2010* -
## Physics

"What happens to the energy associated with a wave after the wave has been damped out?" I'm assuming all the energy is lost by then, am I right?

*asked on July 20, 2010* -
## Biology - Pregnancy

"If the ovaries were removed between the start of pregnancy and the second month then.....because....." "If the ovaries were removed after the second month....." I'm confused because I thought that once pregnancy begins, no more ovulation occurs until

*asked on March 16, 2010* -
## Chemistry

I am predicting acid-base equilibria using the Brondsted-Lowry predictions. I am asked to do "solid aluminum sulfate added to water". So I know there is an Al^2+ ion and a SO4^-2 ion, but does water dissociate into H30^+ and OH^-? If so, then H30^+ and

*asked on May 7, 2010* -
## Physics

"A 5000kg helicopter accelerates upwards at 0.50m/s^2 while lifting a 2000kg car. What is the lift force exerted by the air on the propellers?" I don't understand what the problem is asking for.

*asked on July 12, 2010* -
## Physics

"Vibrators A and B are sources of waves with different wavelengths and they are placed close to one another in a ripple tank. Waves from source A have a wavelength of 8.0cm while those from B have a wavelength of 10cm. The waves start out in phase with

*asked on July 21, 2010* -
## Chemistry

"A mass of 45.0g of molten silver at its melting point is poured into 750mL of calorimeter water at 25.0C. The final temperature reached by both is 30.0C. If the specific heat capacity of silver is 0.235 kJ/kgC, calculate the molar heat of solidification

*asked on February 24, 2010* -
## ALGEBRA

1, Factor each expression x^2 - 10x - 24 A. (x + 4)(x - 6) B. (x + 6)(x - 4) C. (x + 2)(x - 12) D. (x + 12)(x - 2) 2, x^2 - 36 = 0 A. (1 + square root of 3, 1 - square root of 3) B. (-6,6) C. No solution D. None of these 3, Factor each expression 49 x^9 -

*asked on December 11, 2007* -
## Calculus

"A rectangle is inscribed in a semicircle of radius 2 cm. Find the largest area of such a rectangle". There is a diagram, but I think the question makes it clear enough what is going on. I'm having problems finding a relationship that I can work with.

*asked on March 9, 2010* -
## physics

An underwater micriphone is used to record sounds emitted by porpoises. The minimum intensity level the instrument can record is 30.9dB. Assuming a porpoise emits sound at a rate of 0.0603J/s, what is the maximum distance at which the animal will still be

*asked on April 9, 2013* -
## Physics

"Determine the restoring force of a pendulum that is pulled to an angle of 12.0 degrees left of the vertical. The mass of the bob is 300.0g."

*asked on July 26, 2010* -
## Social - History

During the Italian unification, Garibaldi completed the unification of Southern Italy. I've read several resources, but I'm still unclear of how he accomplished that. Did he simply invade Sicily, Naples, and the Papal States? As well, I read somewhere that

*asked on January 13, 2010* -
## Math

Two cards are selected without replacement from a standard deck of 52 cards. What is the probability that the first card selected is either red or a face card?

*asked on December 15, 2009* -
## Physics

"At what point between two masses of 20kg and 15kg located 1.0m apart, will the gravitational field strength equal zero?"

*asked on July 29, 2010* -
## Chemistry

Which solution has the lower freezing point? (a) 90.0 g CH3OH in 100. g H2O 180.0 g CH3CH2OH in 200. g H2O (b) 70.0 g H2O in 1.00 kg CH3OH 70.0 g CH3CH2OH in 1.00 kg CH3OH delta T = Kf m convert 90 g CH3OH to mols mols/kg solvent = m (kg solvent = 0.1) do

*asked on January 21, 2007* -
## Biology

"Suggest two things a large cell might do to increase its surface area:volume ratio". The obvious method would be to divide into many smaller cells...but what else can the cell do? I also thought that it could just simply grow larger, but the question

*asked on March 30, 2010* -
## Biology - Uncertainty

I'm doing a bio lab, and I have collected data on heart rate measured in beats/15 secs with an uncertainty of +/- 1 beat/sec. To get heart rate per minute, I multiplied my data by 4, making my uncertainty +/- 4 beats/min. However, what I need to do now is

*asked on February 9, 2011* -
## Physics

I'm learning about Newton's Laws of Motions and I'm having trouble understanding these questions: "A rear-end collision between a soft-drink truck and a car occurs. The truck driver claims the car backed into him, while the auto driver claims that the

*asked on July 8, 2010* -
## Chemistry

"Translate the empirical molar enthalpy given below into a balanced chemical equation, including the enthalpy change (delta H): The standard molar enthalpy of formation for carbon disulfide is 89.0 kJ/mol" I got delta H = 178 kJ (is that right?). However,

*asked on February 12, 2010* -
## Physics - Another Question

"A meter stick is held vertically behind an object on a spring. The object vibrates from the 20cm mark to the 32cm mark on the stick. Find the displacement when the object is at the 20cm mark, 24cm mark, 26cm mark, and 30cm mark." I had found the

*asked on July 20, 2010* -
## Physics

"Two masses, 2000kg and 5000kg, are placed 20m apart. A third mass of 5000kg is placed in between the two large masses a distance of 5.0m from the larger mass. What is the force acting on the 500kg mass?"

*asked on July 17, 2010* -
## Physics - Projectile Motion

"A person fires a bullet horizontally from a gun at the same instant that another bullet is dropped from the same height as the rifle barrel. Discuss which bullet will hit the ground first." I'm thinking that the bullet that is dropped will hit first,

*asked on July 7, 2010* -
## Physics - Another Question

"An airplane if flying level at 80.0m above the ground with a speed of 350km/h. The bombardier wishes to drop food and medical supplies to hit a target on the ground. At what horizontal distance from the target should the bombardier release the supplies?"

*asked on July 7, 2010* -
## physics

An underwater micriphone is used to record sounds emitted by porpoises. The minimum intensity level the instrument can record is 30.9dB. Assuming a porpoise emits sound at a rate of 0.0603J/s, what is the maximum distance at which the animal will still be

*asked on April 9, 2013* -
## physics

An underwater micriphone is used to record sounds emitted by porpoises. The minimum intensity level the instrument can record is 30.9dB. Assuming a porpoise emits sound at a rate of 0.0603J/s, what is the maximum distance at which the animal will still be

*asked on April 9, 2013* -
## physics

*asked on April 9, 2013* -
## Biology - Uncertainty (Repost)

I'm doing a bio lab, and I have collected data on heart rate measured in beats/15 secs with an uncertainty of +/- 1 beat/sec. To get heart rate per minute, I multiplied my data by 4, making my uncertainty +/- 4 beats/min. However, what I need to do now is

*asked on February 10, 2011* -
## Chemistry

"An aqueous sodium borate solution is titrated to the second endpoint with 0.225 mol/l nitric acid in the presence of a suitable indicator. If an average of 12.6mL of titrant are required to reach the second endpoint for a 25.0 mL sample, what is the base

*asked on May 15, 2010* -
## Math

"In vase A, there are 3 red balls and 5 white balls. In vase B, there are 6 red balls and 4 white balls. Two balls are to be drawn at random, without replacement, from each vase. What is the probability of selecting 4 red balls?" (Answer: 1/28) So I

*asked on May 3, 2010* -
## French

How do you say "I'm just kidding" or "I'm just joking" (something along those lines) in French?

*asked on December 18, 2009* -
## Physics

Why is more fuel required for spacecraft to travel from the earth to the moon than to return from the moon to the earth?

*asked on November 6, 2016* -
## science/chemistry

Qc for the following chemical reaction 3CIO2-(aq)2CIO3-(aq)+Cl-(aq) Choices A:3[CIO2-]/2[CIO3-][Cl} B:2[CIO3-][Cl]/3[CIO2-] C:[CIO2-]^3/[CIO3-]^2[Cl-] D:[CIO3-]^2[Cl-]/[CIO2-]^3 I like B: what would you go for?? thanks all

*asked on May 10, 2010* -
## Chemistry

DrBob, if you're still on...what do I do for NaCl??

*asked on May 2, 2010* -
## Calculus

"Evaluate the following indefinite integrals: "S" (3x^2 -2)/(x^3 - 2x + 1)^3 dx" We're practicing the substitution rule, and I know how to do it, but I don't know what/how to substitute in this question. btw: "S" is the integral sign.

*asked on April 11, 2010* -
## Chemistry

I am designing a lab right now, and I want to know: if I fill a beaker with cold water from the tap and submerge a sample of solid metal, after a couple of minutes, the metal should be the same temp as the water, right? Would it be quicker to use hot water

*asked on February 19, 2010* -
## Math

Eight men enter a doubles tennis tournament in which partners are selected by lot. What is the probability that two brothers, Sean and Kevin, will be selected as partners?

*asked on December 15, 2009* -
## Accounting

How would an auditor go about assessing the quality of an organizationâ€™s corporate governance?

*asked on September 7, 2007* -
## Physics

Describe the steps necessary to convert a parabolic decreasing curve to a liner graph. That's is one with the relationship between two variables give a straight line.

*asked on October 2, 2016* -
## physics

*asked on April 9, 2013* -
## Physics

"Point S1 and S2 are close sources of circular water waves each of wavelength 6.0cm. P is a point some distance away from the sources. Explain whether the following path differences (path difference = PS2 - PS1) result in nodes or anti-nodes. a) 6.0cm b)

*asked on July 21, 2010* -
## English - Macbeth

In Act 3, scene 3, Macbeth sends a third murderer to help the other two murder Banquo and his son. Does the third murderer know as much about Banquo as Macbeth says he does? From what I see, it seems as if it could go either way. For example, this part:

*asked on May 11, 2010* -
## Chemistry

"Calculate the pH of 0.10 mol/L aqueous solution of aluminum sulfate." I am also given the ka value for the aluminum ion (9.8x10^-6)...but I don't know why I need it. I'm not even sure if I need to use it. Help please?

*asked on May 1, 2010* -
## calculus

The manager of a large apartment complex knows from experience that 100 units will be occupied if the rent is 350 dollars per month. A market survey suggests that, on the average, one additional unit will remain vacant for each 7 dollar increase in rent.

*asked on April 20, 2010* -
## Calculus

"Find the volume of the solid generated by revolving the region bounded by the graphs of the given equations about the indicated lines: y = 2x^2 y = 0 x = 2 About the line y = 8"

*asked on April 18, 2010* -
## Calculus

"The line x+y = 0 is tangent to the graph of y = F(x). Find F(x) if F'(x) = x". I know how to find the antiderivative of F'(x), but I don't know how to use the tangent line to find my constant.

*asked on April 3, 2010* -
## Calculus

Differentiate x5^sqrt(x). Help please!

*asked on March 22, 2010* -
## Chemistry

How do I find the concentration of the excess reagent? I already have the moles of excess reagent. I'm stuck because I don't know how to find the volume of excess (I'm not given a density).

*asked on February 4, 2010* -
## Chemistry

Thank you Dr Russ for you answer. Anyone who can answer: I have the moles of excess reagent, but now I need to find the concentration of excess reagent. I know concentration is mol/L, but how do I find the volume of my excess?

*asked on February 3, 2010* -
## Biology

When oxygen uptake is low, a high proportion of the total amount of blood pumped goes to the intestines. When oxygen uptake is high, a small proportion of blood goes to the intestines. Explain the differences in terms of the needs of the body during rest

*asked on December 21, 2009* -
## AP physics

The sun is below us at a magnitude of nearly a line with the earth center. Are we then Heavier at midnight due to the sun's gravitational force on us, than we are at noon? Explain

*asked on November 6, 2016* -
## physics

*asked on April 9, 2013* -
## Math - another question

"In the expansion of (2-ax)^5 the coefficient of x^2 is 5. Find the value of a". I know I have to use the binomial theorem to help me, but I don't know how.

*asked on May 5, 2010* -
## Calculus

"Find the antiderivative of f(x)= (2x)/((x^2)+1)." I understood how to do it with just a number as the numerator, but I can't figure it out with x in the numerator..

*asked on April 1, 2010* -
## Biology

During the follicular stage of the menstrual cycle, both FSH and estrogen are high, but aren't estrogen and FSH on a negative feedback loop? Is it just because FSH is not directly involved in the increase of estrogen (it is the follicle that increases

*asked on March 21, 2010* -
## Chemistry

Do you need to do uncertainties on percent error? It doesn't make sense to have "percent error on percent error".

*asked on February 23, 2010* -
## Calculus

"Find f'(a) for f(x)=(1+2x)/(1+x)" I got 2, but the answer is 1/(1+a)^2. How do I get that??

*asked on February 15, 2010* -
## Math - another question

lim(sqrt(x+1))/(sqrt(4x-1)) as x approaches infinity.

*asked on February 6, 2010* -
## Chemistry

How do you find the moles of excess reactant? I already know the limiting reactant btw.

*asked on February 3, 2010* -
## Biology

What is the function of lactose in the body? I know what lactose is, but I'm having trouble finding if it does anything in the body (give energy...?) And also, what is the function of fructose in plants? I'm having the same problem.

*asked on January 14, 2010* -
## Math

Three balls are drawn together from a bag containing 4 white, 5 black, and 6 red balls. Find the probability that they include no white ball.

*asked on December 16, 2009* -
## Math

A pizzeria offers 8 different ingredients on its pizza. Andy chooses 3 different ingredients from the 8 by drawing the names from a hat. What is the probability that Andy chooses either mushrooms or pepperoni or both among his three ingredients? The answer

*asked on December 16, 2009* -
## AP physics

The earth moves faster in its orbits around the sun in January, or in July? Explain [Note: this is not much of a factor in producing seasons - the main factor is the tilt of the earths axis relative to the plane of its orbit.]

*asked on November 6, 2016* -
## French

I've been given an article and some questions to answer. One of them is: "Au paragraphe deux que veulent dire les mots... a) enjeux b) nouvelle" I can't figure out what the question is asking me to do with those two words.

*asked on October 6, 2010* -
## Math - Caculus

How do I evaluate the limit of e^tan(t) as t approaches pi/2 from the positive side?

*asked on March 19, 2010* -
## Chemistry

If the molecular mass for a chemical is 153.82 g/mol and the enthalpy of formation is -135 kJ/mol, the heat change will be _____ kJ when 10.0 g of this chemical is formed.

*asked on February 20, 2010* -
## Chemistry

If I'm going to transfer a piece of metal (a reasonable size) from a beaker of boiling water into a calorimeter, what should I use? Tweezers are too small...I can only think of a beaker clamp, but they are, after all, for beakers.

*asked on February 19, 2010*

## Pages

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