# chan

Popular questions and responses by chan-
## physics

An AC voltage of the form Δv = (100 V) sin(1000t) is applied to a series RLC circuit. Assume the resistance is 400 , the capacitance is 4.60 µF, and the inductance is 0.500 H. Find the average power delivered to the circuit. W

*asked on December 2, 2013* -
## Math related rates

Water is poured into a conical paper cup at the rate of 3/2 in3/sec (similar to Example 4 in Section 3.7). If the cup is 6 inches tall and the top has a radius of 4 inches, how fast is the water level rising when the water is 2 inches deep? I got

*asked on March 2, 2017* -
## physic

Need Help please. Consider the following mass distribution where the x and y coordinates are given in meters: 5.0 kg at (0.0, 0.0) m, 3.0 kg at (0.0, 4.3) m, and 4.0 kg at (2.8, 0.0) m. Where should a fourth object of 8.2 kg be placed so the center of

*asked on November 23, 2009* -
## linear approximation

Approximate cos (2π/13) by using a linear approximation with f (x) =cos x. cos (2π/13)≈ f(a) + f ' (a)·h = c, what is h, a, and c? I'm having problems with this one please help

*asked on March 2, 2017* -
## physics

A loaded truck is going at a speed of 36 km/hr and a car starts at point 3 km behind the truck with an acceleration of 2 m/s. when will the car overtake the car? What is the distance covered by the car before it overtakes the car?

*asked on July 3, 2012* -
## Chemistry

Calculate the molarity (M) of the following solutions: 4.00moles of glucose in 3.00L of glucose solution 5.50g of KOH in 4.00L of KOH solution 5.85g of NaCl in 400.mL of NaCl solution

*asked on April 7, 2015* -
## math

In how many ways can the letters of the word FACTORING be arranged, without changing the order of the vowels a, o, i

*asked on August 2, 2014* -
## physic

A 660 N cat burglar is supported by cables in the figure below. Assume the angle è of the inclined cable is 36.0°. Find vertical cable? Thank you so much for your help.

*asked on October 12, 2009* -
## Science

A uniform metal ball (mass m) is tied to the end of a string (massless, length L). The other end of the string is fixed. The ball is moving in a vertical circle centered at the fixed end of the string. Suppose the velocity of the ball at the lowest point

*asked on May 3, 2016* -
## Chemistry

How do I calculate number of moles of K2C2O4 in 20mL of a saturated (300g K2C2O4.H2O per liter) solution....

*asked on September 16, 2010* -
## physics

Please, anyone help me please. Q: An object is placed 17.8 cm from a first converging lens of focal length 13 cm. A second converging lens with focal length 24 cm is placed 10 cm to the right of the first converging lens. (Take the direction to the right

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

Determine the volume, in milliliters, required to prepare each of the following diluted solutions. 40.0mL of a 2.75M KNO3 solution using a 1.00M KNO3 solution 45.0mL of a 2.90M H2SO4 solution using a 6.00M H2SO4 solution 0.700L of a 2.10M NH4Cl solution

*asked on April 7, 2015* -
## Chemistry

How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s)-- 3Fe(s) + Al2O3(s)

*asked on December 9, 2012* -
## physics

Hi! could anyone help me to solve this problem please. Three point charges are located at the corners of an equilateral triangle as in the figure below. Find the magnitude and direction of the net electric force on the 1.60 µC charge. (A = 1.60 µC, B =

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

Hi!could anyone help me with this problem please because I been trying so many time and did not get it. Greatly appreciate it. Thank. A 11.2 g bullet is fired horizontally into a 94 g wooden block initially at rest on a horizontal surface. After impact,

*asked on November 2, 2009* -
## physic

Hi, could you help me please Question: A tortoise can run with a speed of 0.12 m/s and a hare can run 20 times as fast. in a race, they both start at the same time, but the hare stops to rest for 2.0 minutes. The tortoise wins by a shell (25cm). A.How long

*asked on September 24, 2009* -
## chem

Cesium-137 is part of the nuclear waste produced by uranium-235 fission. The half-life of cesium-137 is 30.2 years. How much time is required for the activity of a sample of cesium-137 to fall to 25.1 percent of its original value?

*asked on September 10, 2017* -
## math

There were 336 people at a concert. if 2/3 were children, how many chairs were needed for adults?

*asked on February 9, 2016* -
## Chemistry

How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s)-- 3Fe(s) + Al2O3(s)

*asked on December 9, 2012* -
## chemistry

what is the equation of the reaction between potassium sulphite and bromine

*asked on July 11, 2011* -
## physics

Hi! could any help me please, thank you. 1.An object is placed 17.8 cm from a first converging lens of focal length 13 cm. A second converging lens with focal length 24 cm is placed 10 cm to the right of the first converging lens. (Take the direction to

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

Help me please.Thank you so much A uniform plank of length 2.00 m and mass 25.0 kg is supported by three ropes, as indicated by the blue vectors in the figure below. Find the tension in each rope when a 715 N person is 0.500 m from the left end. T1 have

*asked on November 22, 2009* -
## physic

please help me.A 5.00 g object moving to the right at +20.0 cm/s makes an elastic head-on collision with a 10.0 g object that is initially at rest. (a) Find the velocity of each object after the collision. 5.00 g object 10.0 g objectt (b) Find the

*asked on October 28, 2009* -
## physic

A 0.34 kg particle has a speed of 2.0 m/s at point A and kinetic energy of 7.5 J at point B. (a) What is its kinetic energy at A? _____ J (b) What is its speed at point B? _____ m/s (c) What is the total work done on the particle as it moves from A to B?

*asked on October 20, 2009* -
## physic

Find the acceleration reached by each of the two objects shown in figure below if the coefficient of kinetic friction between the 7.00 kg object and the plane is 0.270.

*asked on October 16, 2009* -
## physic

An object with mass m1 = 5.00 kg, rests on a frictionless horizontal table and is connected to a cable that passes over a pulley and is then fastened to a hanging object with mass m2 = 10.0 kg, as shown in the figure below. Find the acceleration of each

*asked on October 15, 2009* -
## physic

A projectivle is launched with an initial speed of 40m/s at an angle of 35 degree above the horizontal. The projectitile lands on a hillside 4s later. negelct air friction. a.What is the straight-line distance form where the prjectile was launched to where

*asked on September 30, 2009* -
## 7th grade

what is a process used to investigate the world around you?

*asked on October 9, 2008* -
## calculus

For what positive numbers will the square of a number exceed twice the number?

*asked on August 4, 2008* -
## chemisty

What is the half-life of polonium-218 if 5.37 minutes are required for the activity of a sample of polonium-218 to fall to 29.5 percent of its original value?

*asked on September 10, 2017* -
## chemisty

Chromium-51 is a radioisotope that is used to assess the lifetime of red blood cells The half-life of chromium-51 is 27.7 days. If you begin with 30.1 mg of this isotope, what mass remains after 44.6 days have passed?

*asked on September 10, 2017* -
## Maths

Find the Taylor formula up to n=3 for f(x)=sin(x) at X0=pi/3: sin(x)=a0+a1(x-pi/3)+a2(x-pi/3)^2+a3(x-pi/3)^3+R3 Use this formula to find the approximate value of sin(58 degees)

*asked on April 6, 2017* -
## Related Rates

(A poignant problem) A 3-foot-tall observer holds a balloon 1 foot in front of her face. Experimentally, the observer releases the balloon and watches as it rises vertically at 5 feet per second. 2 seconds after releasing the the balloon, the observer

*asked on March 2, 2017* -
## Science

I need help with questions regarding information about the Galapagos Island volcano. 1. where is the volcano located 2. how long has it been active 3. what kind of volcano is it 4. is it dangerous 5. what is the surrounding area like 6. what else is there

*asked on May 27, 2015* -
## Chemistry

What is the molarity of a solution containing 10.g of NaOH in 700.mL of NaOH solution? Express your answer to two significant figures and include the appropriate units.

*asked on April 7, 2015* -
## science

Explain why the boiling point of ethyl alcohol (C2H5OH, 78.4 oC) is higher than the boiling point of methyl alcohol (CH3OH, 64.7 oC).

*asked on December 30, 2014* -
## science

Consider the following reaction: CaCO3(s) --> CaO(s) + CO2(g) A mixture of calcium oxide (CaO) and calcium carbonate (CaCO3) had a mass of 15.08 g and was heated to above 840 oC. After heating, 9.83 g of solid was left. What is the mass percentage of

*asked on December 30, 2014* -
## CHEM

Consider the following reaction: 3Pb(NO3)2(aq) +Al2(SO4)3(aq) ¡÷ 3PbSO4(aq) + 2Al(NO3)3(aq) Determine the mass (in gram) of lead(II) sulphate (PbSO4) and aluminium nitrate [Al(NO3)3] formed in the solution when 8.84 g of lead(II) nitrate [Pb(NO3)2] was

*asked on December 30, 2014* -
## CHEM

Hydrogen peroxide (H2O2) is decomposed according to the following reaction: 2H2O2 (l) ¡÷ 2H2O (l) + O2 (g) If 6.00 g of aquesous solution containing hydrogen peroxide was decomposed after heating, the mass of oxygen gas collected is 2.40 g, what is the

*asked on December 30, 2014* -
## Math, Fourier Series

For Fourier Series of f(x)=sin|x| which is an even function, bn should be 0. However, I solved that b1=1 while the rest of the terms =0, meaning bn=0. Is there a mistake?"

*asked on November 20, 2014* -
## math

Find the number of arrangements of the letters of the word STRENGTH if the order of the consonants must not be changed?

*asked on August 2, 2014* -
## maths

5x+6y=37 2x-3y=-4

*asked on May 14, 2013* -
## Chemistry

How many moles of glucose , C6H12O6, can be "burned" biologically when 10.0 mol of oxygen is available. C6H12O6(s) + 602(g)---6CO2(g) + 6H2O(l)

*asked on December 9, 2012* -
## chemistry

Calculate the number of moles of Al2O3 that are produced when 0.6 mol of Fe is produced in the following reaction. 2Al(s) + 3Fe(s)-- 3Fe(s) + Al2O3(s)

*asked on December 9, 2012* -
## Math

I have a drawing with fractions. What does this mean a scale 1:2. I have to draw that picture a scale 1:2. What does that mean?" thank you

*asked on October 21, 2012* -
## Linear equation

Write a linear equation relating x and y x 0 3 6 10 y 2 8 14 22

*asked on October 10, 2012* -
## math

in isosceles angle ABC, the length of leg AB is 2x+10 and the length of the leg BC is 4x - 18. Find the length of each leg.

*asked on October 2, 2012* -
## Geometry

Three line segments have the following measure AB=6, BC=3, and AC=8. What conclusions can you draw about points A,B and C?

*asked on September 24, 2012* -
## Geometry

Let b: Breakfast is a meal Let s: Spring is a season Let h: Halloween is a season s v h = true b ^ s = true ~ s v h = true b ^ ~h = false ~b v ~s = false ~(s ^ h)= false ~(b v ~s) = true ~b ^ ~s = false

*asked on September 12, 2012* -
## physics

An airplane taking off from a landing field has run of 400 m. If it starts from rest and accelerates its motion uniformly and makes the run in 20 seconds. with what velocity did it take off

*asked on July 6, 2012* -
## chemistry

Analyze the properties of a sodium atom and a sodium ion. What are the differences in mass, stability, and reactivity that are caused due to the differences between the sodium atom and sodium ion?

*asked on March 8, 2012* -
## chemistry

why 1/t represent k in iodine clock reaction

*asked on October 22, 2011* -
## QM

I have borrowed a sum of $150000 for buying house at 12% simple interest per year at the beginning of a year.The loan has to be repaid by three payment of $10000,$30000 and $X at the end of February, July and November of the same yaer respectively. Find

*asked on October 15, 2011* -
## chemistry

will potassium chloride react with bromine

*asked on July 11, 2011* -
## Physics

A simple pendulum has a period T on the surface of planet Earth. When taken to the surface of planet X, the same pendulum has a period 2T. a) If the radius of planet X is 1/2 the radius of Earth, what is the mass of Planet X, relative to the mass of Earth?

*asked on May 15, 2011* -
## Calculus ll

Find the radius of convergence and interval of convergence for ‡”(from n=1 to ‡ ) (-1)^n-1 multiplied by n(x-1)^n/(n^2+1)2^n thank you for your help

*asked on April 21, 2011* -
## language

what part of speech is has passed

*asked on November 29, 2010* -
## Math

x(x-3)+4= 3x^2 - 2(x+8) 3

*asked on October 26, 2010* -
## math

(2x^3)-2 3

*asked on October 26, 2010* -
## Science

much force is Mike applying to the 1000 kg car to make it accelerate at a rate of .05 m/s2? I need help understanding this.. I'm really bad at science...>.

*asked on October 22, 2010* -
## physics

Hi! could anyone help me to solve this problem please. Thank you. Question:An electron has a speed of 0.68 c. (a) Find the speed of a proton that has the same kinetic energy as the electron. (b) Find the speed of a proton that has the same momentum as the

*asked on May 6, 2010* -
## physics

Hi! could anyone please help me with this problem. Thank you so much. Q: The critical angle for total internal reflection for ice surrounded by air is 49.8°. Calculate the Brewster angle for ice if the light is incident from the air.

*asked on April 25, 2010* -
## Physics

Hi! Need help please, thank you. Question:In a model AC generator, a 498 turn rectangular coil 14.0 cm by 21 cm rotates at 124 rev/min in a uniform magnetic field of 0.65 T. (a) What is the maximum emf induced in the coil? ___ V (b) What is the

*asked on March 15, 2010* -
## physics

Hi! could anyone help me with this question please, I really don't know how to do this at all. Thank you so much. Question:A 330 turn solenoid with a length of 21.0 cm and a radius of 1.40 cm carries a current of 2.10 A. A second coil of four turns is

*asked on March 15, 2010* -
## physics

Hi! could anyone help me please, I have no idea how to this at all. I try to it but, the did not get the right answer. Thank for your help Oppositely charged parallel plates are separated by 5.34 mm. A potential difference of 600 V exists between the

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

Hi!could anyone help me please, Thank. Gas in a container is at a pressure of 1.3 atm and a volume of 1.0 m3. (a) What is the work done on the gas if it expands at constant pressure to twice its initial volume? (b) What is the work done on the gas if it is

*asked on December 7, 2009* -
## physics

Hi, could anyone help me please, Thank. Gas in a container is at a pressure of 1.3 atm and a volume of 1.0 m3. (a) What is the work done on the gas if it expands at constant pressure to twice its initial volume? (b) What is the work done on the gas if it

*asked on December 6, 2009* -
## physic

Hi! Help me please, thank you so much. What mass of water at 28.0 °C must be allowed to come to thermal equilibrium with a 2.05-kg cube of aluminum initially at 1.50 102 °C to lower the temperature of the aluminum to 54.8 °C? Assume any water turned to

*asked on December 3, 2009* -
## physic

Hi! help me please, Thank you. A spherical steel ball bearing has a diameter of 2.540 cm at 23°C. (a) What is the diameter when its temperature is raised to 94°C? cm (b) What temperature change is required to increase its volume by 0.9%? I only need help

*asked on December 1, 2009* -
## physic

HI!can anyone help me please, just on part b.Thank you so much. A spherical steel ball bearing has a diameter of 2.540 cm at 23°C. (a) What is the diameter when its temperature is raised to 94°C? ___ cm (b) What temperature change is required to increase

*asked on November 30, 2009* -
## physic

Hi! I really need help on Part B only. (a) Calculate the absolute pressure at the bottom of a freshwater lake at a depth of 28.7 m. Assume the density of the water is 1.00 103 kg/m3 and the air above is at a pressure of 101.3 kPa. (b) What force is exerted

*asked on November 28, 2009* -
## physic

Hi! need help please thank you so much. Question:(a) Calculate the absolute pressure at the bottom of a freshwater lake at a depth of 28.7 m. Assume the density of the water is 1.00 103 kg/m3 and the air above is at a pressure of 101.3 kPa. ___Pa (b) What

*asked on November 26, 2009* -
## physic

hi,need help please.thank. A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 2.00 m and a mass of 525 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up

*asked on November 23, 2009* -
## physic

hi,need help please.thank. A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 2.00 m and a mass of 525 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up

*asked on November 22, 2009* -
## physics

hi,need help please.thank. A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 2.00 m and a mass of 525 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up

*asked on November 22, 2009* -
## physic

Hi,could anyone help me with this questin please. Thank you so much. some folks on your planet waant to travel to the moon.But what happens to their clocks, it they leave the Earth?for other bodies, like the moon or planets the acceleration due to gravity

*asked on November 20, 2009* -
## physic

Hi! could you help this problem please try so many time but, the answer is not correct. Question:The tires on a new compact car have a diameter of 2.0 ft and are warranted for 62,000 miles. (a) Determine the angle (in radians) through which one of these

*asked on November 15, 2009* -
## physic

Hi! could you help this problem please try so many time but, the answer is not correct. Question:The tires on a new compact car have a diameter of 2.0 ft and are warranted for 62,000 miles. (a) Determine the angle (in radians) through which one of these

*asked on November 15, 2009* -
## physic

Hi!Need help please. Question:A car initially traveling at 24.0 m/s undergoes a constant negative acceleration of magnitude 2.10 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the

*asked on November 14, 2009* -
## physic

Hi!could anyone help me please, I don't get it. Thank you so much for your help. Question:(a) What is the tangential acceleration of a bug on the rim of a 9.0 in. diameter disk if the disk moves from rest to an angular speed of 79 rev/min in 4.0 s? ___m/s2

*asked on November 13, 2009* -
## physic

Hi! could you help me to start this problem becuase I had try so many time and did not get it right at all please. Thank you so much. A rifle with a weight of 20 N fires a 4.0 g bullet with a speed of 260 m/s. (a) Find the recoil speed of the rifle. (b) If

*asked on October 29, 2009* -
## physic

Hi! I try already but, the answer is wrong could you help me to fix it out. A sledge loaded with bricks has a total mass of 17.8 kg and is pulled at constant speed by a rope inclined at 20.8° above the horizontal. The sledge moves a distance of 20.6 m on

*asked on October 27, 2009* -
## physics

Two blocks, A and B (with mass 50 kg and 100 kg, respectively), are connected by a string, as shown in the figure below. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between block A and the incline is µk = 0.24.

*asked on October 26, 2009* -
## physic

please help, I really appriciate you help alot. Question:A 0.34 kg particle has a speed of 2.0 m/s at point A and kinetic energy of 7.5 J at point B. (a) What is its kinetic energy at A? ___ J (b) What is its speed at point B? ____ m/s (c) What is the

*asked on October 24, 2009* -
## physic

Please help me I have no idea how to do this problem at all. Question:A sledge loaded with bricks has a total mass of 17.8 kg and is pulled at constant speed by a rope inclined at 20.8° above the horizontal. The sledge moves a distance of 20.6 m on a

*asked on October 24, 2009* -
## physic

A block of mass 12.0 kg slides from rest down a frictionless 34.0° incline and is stopped by a strong spring with k = 2.5 104 N/m. The block slides 3.00 m from the point of release to the point where it comes to rest against the spring. When the block

*asked on October 21, 2009* -
## physic

Hooke's law describes a certain light spring of unstretched length 30.0 cm. When one end is attached to the top of a door frame, and a 8.40-kg object is hung from the other end, the length of the spring is 40.00 cm. (a) Find its spring constant. ____ kN/m

*asked on October 21, 2009* -
## physic

Hi! please help A sledge loaded with bricks has a total mass of 17.8 kg and is pulled at constant speed by a rope inclined at 20.8° above the horizontal. The sledge moves a distance of 20.6 m on a horizontal surface. The coefficient of kinetic friction

*asked on October 20, 2009* -
## physic

The coefficient of static friction between the m = 3.20 kg crate and the 35.0° incline of the figure below is 0.340. What minimum force must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline?

*asked on October 16, 2009* -
## physic

An object with mass m1 = 5.00 kg, rests on a frictionless horizontal table and is connected to a cable that passes over a pulley and is then fastened to a hanging object with mass m2 = 10.0 kg, as shown in the figure below. Find the acceleration of each

*asked on October 16, 2009* -
## physic

Two forces are applied to a car in an effort to move it, as shown in the following figure, where F1 = 439 N and F2 = 365 N. (Assume up and to the right as positive directions.) (a) What is the resultant of these two forces? magnitude___ N direction ____°

*asked on October 15, 2009* -
## physic

Hi!Two forces are applied to a car in an effort to move it, as shown in the following figure, where F1 = 439 N(10degree) and F2 = 365 N(30degree). (Assume up and to the right as positive directions.) (a) What is the resultant of these two forces?

*asked on October 12, 2009* -
## physic

Hi!Question:Two packing crates of masses m1 = 10.0 kg and m2 = 6.50 kg are connected by a light string that passes over a frictionless pulley as in the figure below. The 6.50 kg crate lies on a smooth incline of angle 45.0°. Find the acceleration of the

*asked on October 9, 2009* -
## physic

Hi!An object with mass m1 = 5.00 kg, rests on a frictionless horizontal table and is connected to a cable that passes over a pulley and is then fastened to a hanging object with mass m2 = 10.0 kg, as shown in the figure below. Find the acceleration of each

*asked on October 9, 2009* -
## physic

Hi!Question:The helicopter view in the fiure below shows two people pulling on a stubborn mule. Asume that F1 is 110N, and F2 si 70N. The forces are measured in units of newtons(N). a.Find the single force that is equivalent to the two forces shown.

*asked on September 30, 2009* -
## physic

Hi!Question: A river flows due east at 1.70m/s.A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 8.0m/s due north relative to the water. A.What is the velocity of the boat relative to shore?___m/s and

*asked on September 30, 2009* -
## physic

Hi! Question:A ball is tossed from an upper-story window of a building.The ball is given an initial velocity of 7.80m/s at an angle of 21.0 degrees below the horizontal.It strikes the ground 3.00s later. A.How far horizontally from the base of the building

*asked on September 30, 2009* -
## Physic

A ball is thrown vertically upward with a speed of +12.0m/s. A. how long the ball take to hit the ground after it reaches it highest point? B. What is its velocity when it returns to the level from with it started?

*asked on September 23, 2009* -
## eth125

How do you think slavery influenced the evolution of both black and white america today?explain your answer.

*asked on September 21, 2009* -
## calculus

How do I find the domain of: y=squareroot of x^3-3x^2 ?

*asked on August 4, 2008*