129,881 results, page 50

1. ### Physics

two binary stars moving in a perfect circle orbit The stars have the same mass, the distance between them is one billion km (1x10^9 km), and the time each takes for one orbit is 10.4 Earth years. Determine the mass of each star (m1=m2). (this problem DOESN'T uses the gravity ...
2. ### Physics

Hi everybody! I need this quick answer, please help! The beam AB in the figure has length 3L and uniform section stiffness EI. The beam is fixed at A(x=0) and loaded by an upward concentrated force, P, applied at its free end B(x=3L). A concentrated moment Q is also applied, ...
3. ### Sorry- Chemistry / Ionic Bonding

Hello My exams are coming I'm a straight A student .. the problem however is : My textbooks , teacher and every piece of work that he gives us is complicated can someone explain me how Ionic Bonding works . Please I really beg you... I need your help! My teacher sucks in ...
4. ### precalculus

the population of a country is 65 millions if it grows exponentially in a rate of 1.5% annual 1.-calculate the estimate population in 12 years 2.-when the population increases 4 times could somebody please explain me this kind of problems where you need to use the log and ...
5. ### Ms, Sue please respond

I had posted a serious letter of a real situation that happenned. I sm trying to write this letter for that reason. I am not sure where it will seem like an excuse if i bring the forms. please suggest a better way of writing the letter.
6. ### math

sums and differences of rational algebraic expression answer the following perform the indicated operation reduce answers to lowest term 2x/x^2-2x-15 - x-2/3x^2+9 another is t/2rs^2 - 2r/3rst + 3s/30r^2t another is 3x/2x-3 - 2x/2x+3 + 3/4x^2-9 please answer this i need it ...
7. ### Physics, still don't get it!

Suppose a monatomic ideal gas is contained within a vertical cylinder that is fitted with a movable piston. The piston is frictionless and has a negligible mass. The area of the piston is 3.06 10-2 m2, and the pressure outside the cylinder is 1.02 105 Pa. Heat (2109 J) is ...
8. ### Physics - electricity

An incandescent lamp is marked '120v,75W' a)what is the current in the lamp under normal condition of operation? b)How much does it cost per hour to operate the lamp if the price of electrical energy is \$6.00 per unit? Please stop posting under different names. Use ohms law, ...
9. ### physics

A stone is observed falling past a small window 1 meter tall in 0.2 seconds. how fast is it moving as it passes the bottom of the window?how far is the bottom of the window from the roof, where the stone originally began its fall from rest?what is the stone's average speed as ...
10. ### Nuclear physics

1) An old wooden tool is found to contain only 11.9 percent of 14C that a sample of fresh wood would. How many years old is the tool? 2) A specimen taken from the wrappings of a mummy contains 7.02 g of carbon and has an activity of 1.34 Bq. How old is the mummy? Determine its...

Sorry for re-posting but I really need to know if I did it right. Please someone help! Two 3.0g bullets are fired with speeds of 40.0 m/s and 80.0 m/s respectively. What are their kinetic energies? Which bullet has more kinetic energy? What is the ratio of their kinetic ...
12. ### PHYSICS-LAW OF THERMODYNAMICS

A dinner plate drops and breaks. This best illustrates the ______ law of THERMODYNAMICS A. 1st b. 2nd c. 3rd d. 4th I am inclined to say the 1st because energy can be neither created nor destroyed, it can only change forms. Thus the plate falling lost it's energy as a whole, ...

A small spherical insulator of mass 8.96 10-2 kg and charge +0.600 μC is hung by a thread of negligible mass. A charge of −0.900 μC is held 0.150 m away from the sphere and directly to the right of it, so the thread makes an angle θ with the vertical (see ...
14. ### Subject-verb agreement

which of the following sentences demonstrates proper subject-verb agreement? A. News travel fast. B. Measles usually spread through respiratory fluids. C. Physics is a difficult subject to learn. D. They study of various sciences are compelling. A and D are not correct. C is ...
15. ### physics

A bar 4.0 m long weighs 400. N. Its center of gravity is 1.5 m from one end. A weight of 300. N is attached at the heavy end and a weight of 500. N is attached at the light end. What are the magnitude, direction, and point of application of the force needed to achieve ...
16. ### Physics

A mover finds that a 20 kg crate initially at rest requires a 75 N horizontal force to set the crate in motion, but only a 60 N force to maintain a constant velocity. Find a) the co-efficient of static friction between crate and floor. b) the co-efficient of kinetic friction ...
17. ### critical thinking

how do assumptions relate to the process of critical thinking? Please note that we don't do students' homework for them. Once you have come up with a response to these questions, please re-post and let us know what you think. Then someone here will be happy to critique your ...

Hi, I'm trying to write a good lead for my research paper on Confucius. I'm using the "snapshot" method. So, I need an important event in Confucius' life that I can describe in writing. PLEASE HELP!!!! THANKS IN ADVAVCE! -aShLeY

I really need someone to look at my previous posts and edit them if they need to be edited. Please point out any grammatical errors. Thank you very much. You will find my posts as soon as you enter my name in the Search Box.

A 0.2mol/L solution of KMnO4 has been added to 10 ml of 0.5mol/L acidified FeSO4. write the balance equation of the reacttion then calculate the volume of the oxidizing solution that should be added to oxidize all the Fe^2+ ions. please help and thank you!!
21. ### Math

Can you please help me select at least five numbers; 0 (zero), two even, and two odd numbers and do a simple substitution of number for variable in a formula. And can you explain each step and show the work on how you came up with the answer please thank you.
22. ### integral Calculus

ʃ (4sin²x cos²×/sin2x cos2x)dx i've got it from the book and it has an answer from the back page of the book but i want to know how to solve it..i really need it for practicing this subject...please please help..Thanks a lot.. the answer is: -1/2 ln|secx + tanx| + c
23. ### health informatics

how is emerging technology influencing healthcare? and give an example. all what i know is that they are basiclly new technologies and my example is about tissue engineering but the problem is that i don't know how it influences the healthcare!!! so please please your help!! i...

given the following piecewise function F(x)={x+11 for -9¡Üx<-3 2 for -3¡Üx¡Ü2 2x-6 for 2<x¡Ü5 {--this symbol is to be around all three of the lines. Find: a. the domain b. the range c. the intercepts d. if f continious on its domain. If not, state where f is ...
25. ### English

Having problems with a introductory sentence. Its a essay on dying and living. I wrote a question to start my intro. Sentence. Or I wrote The professor died in 1974 of Cancer. Someone please let me know if I started out right. Please

I need a variety of tutors opinions and choices of what song they like the best. just write the name of the song amongst with the artist PLEASE SPREAD THE WORD ACROSS AND ANSWER BELOW ASAP!

Please, I desperately need help with these questions. These questions regard "The Rug Merchant" by James A. Michener. 1. Which of Zaqir's words and actions create the vivid portrait of him? 2. What do you learn about Michener's character through his storytelling?
28. ### Calculus Help Please Urgent!!!

find the limit algebraically. Use L'Hospital's Rule where appropriate. If there is a moare elementary method, consider using it. If L'Hospital's Rule doesn't apply, explain why lim -> 0 (cot(x)-(1/x)) show work please!!!
29. ### Algebra 1 Explanation (Anyone, please!)

Please, can anyone explain the concept of graphing quadratic functions to me? For example, how must I graph gradratic functions such as y = x^2 - 2x - 3? If anyone could also include step-by-step solving methods, I would truly appreciate it.

Some constellations, such as Ursa Minor, are visible in the sky year-round; other constellations appear for only part of the year. Explain why this happens. I've been trying to figure it out but I can't please help me!
31. ### Chem

A student mixed 6 g of ice at -3.4 degrees celsius with 1 g of steam at 103 degrees celsius. What was the final temperature of this mixture.i tried equalling mcdelta T. Please help asap. I would be eternally grateful. Please answer in kj or J only
32. ### english

Need help with an assignment please.I am going to explain this to the class and I want to feel confident.Your help is appreciated. Its Allusion. I picked "Someone who perservers and never gives up." I have to identify what it means, and researh their story, the one the writer ...

A painter climbs a ladder leaning against a smooth wall. At a certain height, the ladder is on the verge of slipping. Let the mass of the painter be 69.0 kg, length = 2.80 m, the ladder’s mass to be 21.0 kg, θ = 57.0°, and the coefficient of friction between ground and...
34. ### Physics

A simple Atwood’s machine uses a massless pulley and two masses m1 and m2. Starting from rest, the speed of the two masses is 4.1 m/s at the end of 7.6 s. At that time, the kinetic energy of the system is 86 J and each mass has moved a distance of 15.58 m. Find the value of ...
35. ### english

Can someone please help me! I have to write an essay and I have to choices one is to write about where did the people of Early America find connections. I don't know where, but if someone can help me find a website, or tell me what happen I will greatly appreciate it. The ...

a.the gravitational force between 2 electrons 1.00m apart is 5.42x10^-71 N. Find the mass of an electron. b.2 spherical balls are placed so their centres are 2.6m apart. The force between the balls is 2.75x10^-12N. What is the mass of each ball if one ball is twice the mass of...
37. ### Physics

A lightning bug flies at a velocity of 0.25m/s due east toward another lightning bug seen off in the distance. A light breeze blows from the east on the bug at a velocity of 0.25m/s. What is the resultant velocity of the lightning bug? Please direct me to even start-I'm ...

An object is inside a room that has a constant temperature of 295 K. Via radiation, the object emits three times as much power as it absorbs from the room. What is the temperature (in kelvins) of the object? Assume that the temperature of the object remains constant. I thought...
39. ### physics

Q1-In hugyen's principle of wave theory why the waves are move in forward direction not in backward direction means they move forward as a new source why not in backward direction? Ans- I think that waves move in forward direction sir i know that only so please give me a ...
40. ### Physics

I am doing this exercise for physics class where I have to place a penny on a ruler and balance it. And I don't understand what is the use of knowing the center mass of an object when making a calculation?
41. ### physics

for a microwave with a wavelength of 3cm, calculate the frequency. Would this number change if physics suddenly broke and the speed of light in air decreased by a factor of 2?
42. ### Physics

7) Find the force of gravity between two 74.0 kg physics students that are sitting 0.85 m apart 7579.24 N 5.057 x 10(-7) N None of these choices are correct 9.8 x 10(-7) N I'm unsure of how to begin.
43. ### physics

A student applies an upward force of 56 N to a 5.6-kg physics textbook. Find the book’s acceleration (positive for up, negative for down). answer in miles/seconds squared.
44. ### physics

A motor car of mass 800kg travelling at 20m/s is brought to rest by brake in 100m.calculate the average braking force required.in physics
45. ### physics

A motor car of mass 800kg travelling at 20m/s is brought to rest by brake in 100m.calculate the average braking force required.in physics
46. ### physics

a motor car of mass 800kg travelling at 20m/s is brought to rest by breakes in 100m.calculate the average breaking force required.in physics
47. ### Physics

The maximum torque experienced by a coil in a 0.90 T magnetic field is 8.4 10-4 N·m. The coil is circular and consists of only one turn. The current in the coil is 3.9 A. What is the length of the wire from which the coil is made? Please tell me if I am going in the right ...
48. ### PHYSICS

HELP. I need to understand this for a test tomorrow. THANKS Consider planet mass of 4.98 E 21 kilograms with a satellite orbitting it at distance of 3.11 E 6 meters from planet's center. Satellite has mass of 369 kilograms. How long (inseconds) does it take the satellite to ...
49. ### Physics

Please, help me with this problem... im a bit confused abt solving it.. In a tank of volume V=7.5 L, temperature T=300 K, there is a mix gases: n1=0.1 mole of oxygen, n2=0.2 mole of nitrogen, n3=0.3 mole of carbon dioxide. Considering the gases ideal, find: (a) the pressure of...

A Foucault pendulum is designed to demonstrate the effect of the Earth's rotation. A Foucault pendulum displayed in a museum is typically quite long, making the effect easier to see. Consider a Foucault pendulum of length 16 m with a 109-kg brass bob. It is set to swing with ...

Some bacteria are propelled by motors that spin hair-like flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.9x10-8m, and a tangential speed at the rim of 2.7x10-5 m/s. (a) What is the angular speed (the magnitude of the angular ...
52. ### Physics

The 56 kg man in the roller coaster car is sitting on a bathroom scale. If he is traveling at 40.9 m/s at the point shown and the radius of the vertical coaster track is 87 meters, to the nearest newton what does the scale read? What is the answer to the previous problem if ...

A right triangle has an area of 13 m2. The dimensions of the triangle are increased by a scale factor of 3. What is the area of the new triangle? Please help!!!! a)39 m2 b)169 m2 c)117 m2 d)142 m2
54. ### SAT

please help. I am a foreigner. I need to get into a US college for a bright future. I bought the College Board SAT book. It has no word lists. How do I do well in the SAT? Any tips? Please give me help.
55. ### Math - Absolute Value Inequalities

Please help me with the following: Which of the following expressions is equivalent to |x – 2| < 3? A. –3 > x – 2 < 3 B. –3 < x – 2 < 3 C. x – 2 < 3 and x – 2 < –3 D. x – 2 < 3 or x – 2 < –3 I know the answer isn't A because I ...
56. ### math

Starting from rest, a 5.00 kg block slides 2.50 m down a rough 30.0 degree incline. The coefficient of kinetic friction between block and the incline is .436. Determine the work done by the friction force between block and incline and the work done on the normal force?

X=(Vo cos Q) t X=(3.107 cos 0)(0.443) I just wanted to make sure that I put this equation into my calculator correctly. I have a TI-30 so first I put in 0 then cos to get 1. Then I multiplied by 3.107 to get 3.107 and then multiplied by 0.443 to get 1.376 . Did I do this ...
59. ### physics

How much heat must be added to 0.55 kg of aluminum to change it from a solid at 180°C to a liquid at 660°C (its melting point)? The latent heat of fusion for aluminum is 4.0x10^5 J/kg. I understand the Equation Q=mc times change it T would that be .55 times 4.0 x 10^5 times...
60. ### physics

a ball is projected horizontally from the edge of a table that is 0.433m high, and it strikes the floor at a point 1.84m from the base of the table. the acceleration of gravity is 9.8m/s^2.what is the initial speed of the ball? how high is the ball above the floor when its ...
61. ### Physics

If a wire of resistance R, resistivity ñ "roe", length L, and cross sectional area A, had its length doubled and radius halved, what would be the ratio of R'/R. Where R' is the new resistance of the wire. I thought it would be 4 times R, giving the ratio of 4R:R' However, I ...
62. ### physics

Two stones are thrown simultaneously, one straight upward from the base of a cliff and the other straight downward from the top of the cliff. The height of the cliff is 6.82 m. The stones are thrown with the same speed of 8.88 m/s. Find the location (above the base of the ...
63. ### Please Check My Work: College Physics

Determine the minimum angle at which a roadbed should be banked so that a car traveling at 20 m/s can safely negotiate the curve if the radius of the curve is 200m. * Data: v=20 m/s r=200m *Formula TAN(theta)=v^2/rg *Solution TAN(theta)=(20 m/s)^2/(200m)(9.8 m/s^2) TAN(theta...

Graph the function. Compare the graph with the graph of f(x)=x q(x)=x-1 How would I do this? Cause, I do know that f is the same thing as y and so that in the problem it'd be y=x-1 right? Could somebody please explain how to do this STEP by STEP?

If one angle in a pair of vertical angles measures 42 degrees and the other measures 2n-4 degrees, which is the value of n? I got 23 degrees but I am not sure if it is correct. Please help me...

simplify the expressions... 1. (x^3)^5 2. (y^4)^5 3. 4^8/4^2(this is a fraction) 4. b^2/b^4(this is a fraction) 5. 28xy^7/32xy^12(this is a fraction) Please show me step by step because I am not really understanding these types of problems...

A container is fitted with a movable piston of negligible mass and radius r = 0.061 m. Inside the container is liquid water in equilibrium with its vapor, as the drawing shows. The piston remains stationary with a 120-kg block on top of it. The air pressure acting on the top ...
68. ### physics - BOB

PLEASE SEE ADDITIONAL QUESTION AT BOTTOM. A pendulum was set up and measurements were made to enable the mechanical energy to be calculated at the start position S and the lowest point of the pendulums swing L. The mass of the pendulum bob was determined on an electronic scale...

A box of weight w=2.0 N accelerates down a rough plane that is inclined at an angle 30 degrees above the horizontal. The normal force acting on the box has a magnitude n= 1.7 N, the coefficient of kinetic friction between the box and the plane is .30, and the displacement d of...
70. ### Math (Physics)

A galaxy is moving away from Earth. The "blue" hydrogen line at 434 nm emitted from the galaxy is measured on Earth to be 458 nm . Part A How fast is the galaxy moving? Answer--> v=____ c Part B How far is it from Earth based on Hubble's law? Answer--> d=____ ly [Please ...

Iron is found in Earths crust as several different iron compounds. Calculate the mass (in kg) of each compound that contains 1.0 x 10E3 kg of iron. Fe2O3 Please help step by step
72. ### Algebra

I can't seem to solve this for x correctly...I got 128 over 55 as an answer which can't be correct. Please help me find the correct answer! Thanks! The equation is: .05x-.6(x+2)=.08 Please show the work as well as the answer. Thanks again.

Sally has three times as many dimes as nickels and twice as many quarters as dimes.In all she has \$5.55. How many coins of each type does she have? Let 2x=quarters 3x=dimes x=nickles <---- is that correct please help put

Hi , I am having a very difficult time finding an article that contains a misconception about evolution . The article had to be be published within in this past year. Please help !!! thank you!!
75. ### physics

A circular wire coil consists of 100 turns and is wound tightly around a very long iron cylinder with a radius of 2.5 cm and a relative permeability of 2200. The loop has a current of 7.5A in it. Determine the magnetic field strength produced by the coil (a) at the center of ...
76. ### Physics

A student states that the velocity of a train is 95 kilometers/hour. What is wrong with that statement? The units should be in kilometers/second/second Velocity must include a speed and direction Velocity is a measure of the change in speed over time. Velocity is the distance ...
77. ### Algebra1

A golfer hits a shot to a green that is elevated 3.0 m above the point where the ball is struck. The ball leaves the club at a speed of 17.4 m/s at an angle of 35.0¢ª above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air ...

A golfer hits a shot to a green that is elevated 3.0 m above the point where the ball is struck. The ball leaves the club at a speed of 17.4 m/s at an angle of 35.0¢ª above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air ...
80. ### 7th grade Lang. Art

Please fill in the blank there will be a list of words below She was so happy and grateful that i felt more than______________for all that i had tried to do to help her. List: alight barren disrupt dynasty germinate hurtle sullen vicious Please help!! Thank you!!1
81. ### Social Studies (Ms. Sue)

Name two geologic obstacles and one political obstacle that stood in the way of the construction of the Panama Cannel. How did engineers and politicians overcome these obstacles. Please don't copy and paste answers I'll except links but please don't give me Wikipedia.
82. ### @ Online Students

A student recently posted this. Please think about it. "quick backstory; i've been cheating on all of my work except portfolios this whole year cause i'm in online school. but i'm wanting to learn since there's gonna be ACT test in REAL so... please help me on how to do this!"
83. ### Math

The exchange rate from US dollars (USD) to euros (EUR) is given by 1 USD = 0.753 EUR. Give the answers to the following correct to two decimal places. Roger receives 800 Australian dollars (AUD) for 610 EUR. Calculate the value of the US dollar in Australian dollars. Please ...

I Don't understand any of this and its due tommorow and i don't get it, can you please help me. 1. 2/3 of a number m 2. The fifth power of 3 times a number y 3. The quotient of twice a nimber t and 12 4. Twice the difference of 8 and a number b.
85. ### social studies

What are some resources that countries in the North have. Please LIST the resources. DON'T give me any sites. I tried to find some resources but I couldn't. Please help me. THANKS!:):):):):):):):):):):):):):)
86. ### FINANCE/MATH

Please use both M&M proposition II with taxes equation and WACC equation to derive the following equation:? WACC = Ru X [1- Tc(D/V)]? I need this by tomorrow please help.
87. ### Differentiation

for the curve x^2+z^2+2gx+2hy=0 value of dy/dx at(0,0) is A. -g/h B. g/h C. h/g D. None Please help me. In the answer page it shows option A as answer. I don't know deeply of differentiation . Please could you help me by explain how the answer is A
88. ### GEOGRAPHY (URGENT!!!)

I NEED HELP!!! this is urgent!!! Human-Environmental Interactions: how did the people in Khartoum modify the environment? how is the people in khartoum being influence by the physical landscape/environment? sorry my grammar sucks i have other questions but i really extremely ...
89. ### PHYSICS

A dolphin wants to swim directly back to its home bay, which is 0.85 km due west. It can swim at a speed of 4.35 m/s relative to the water, but a uniform water current flows with speed 2.82 m/s in the southeast direction. (a) What direction should the dolphin head??? (b) How ...
90. ### Physics

A disk at rest experiences a constant angular acceleration for t = 85 s, at the end of which it is spinning with a frequency of f = 45 rpm. Please answer the following questions. A)Write an expression for the magnitude of the angular velocity of the disk after the acceleration...
91. ### Physics

Can you please explain further because I don't understand? Posted by Mary on Wednesday, November 14, 2007 at 4:23pm. A wavelength of 625 nm is used in a Young's double-slit experiment. The separation between the slits is d = 1.3 10-5 m. The total width of the screen is 0.20 m...
92. ### physics

A variable capacitor is connected to an ac source. what effect does decreasing the capacitance have on the reactance and current in this circuit? Reactance Current A) increases decreases b) decreases no change c) decreases increases d) increases increases e) no change no ...
93. ### physics

help please A sailboat is traveling east at 8.0 m/s. A sudden gust of wind gives the boat an acceleration a = (1.30 m/s2 35° north of east). What is the boat's speed 10.0 seconds later when the gust subsides? What is the boat's direction (in deg) 10.0 seconds later when the ...
94. ### Physics

(a) If the length of the Achilles tendon increases 0.55 cm when the force exerted on it by the muscle increases from 2200 N to 6000 N, what is the "spring constant" of the tendon? N/m (b) How much work is done by the muscle in stretching the tendon 0.55 cm as the force ...

You are looking into the headlights of a distant vehicle on an autoroute in France. The driver has shown his resistance to the Europeanization of Europe by resolutely continuing to use yellow headlights (wavelength 550. nm). a) What is the theoretical limit of angular ...

How many atoms of element "R" are present in 55.80 g of (AH3)4(R2O3)4 (molar mass = 478.17 g/mol)? Please help. I've tried going (g of molecule/mol)x(1 mol of molecule/ 55.80g)but I'm not really sure what to do with this.