Friday

May 27, 2016
Total # Posts: 501

**Physics! - PLEASE HELP**

A 75 kg passenger in a van is wearing a seat belt whent he van moving at 15m/s, collides with a conrete wall. The front end of the van collapses 0.50 m as it comes to rest. a) what was the paseenger's kinetic energy before the crash b) What average force did the seat belt ...
*July 12, 2011*

**Physics - Work**

A tennis racket is in contact with a 55 kg ball for 0.0050 s changes the ball's velocity from 30 m/s [E] to 40 m/s [W] over a distance of 0.0001 m. how much work is done on the tennis ball by the racket?
*July 10, 2011*

**chemistry 101**

17.3 g
*July 8, 2011*

**Physics**

consider a cart being pulled up an inclined plane by a student during a Physics lab. The applied force on the cart is 18 N is directed parallel to the incline to cause the cart to be displaced parallel to the incline for a given displacement of 0.7 m. The initial energy plus ...
*July 8, 2011*

**Physics**

consider a cart being pulled up an inclined plane by a student during a Physics lab. The applied force on the cart is 18 N is directed parallel to the incline to cause the cart to be displaced parallel to the incline for a given displacement of 0.7 m. The initial energy plus ...
*July 8, 2011*

**how to make $60 two ways using 3 coins**

You would have to use a 50 cent coin and then two nickels t equal 60 cents.
*July 6, 2011*

**Physics - Newton's first law**

A pair of fuzzy dice hang from the rear view mirror of a car. For each of the motions indicate which way the dice would move and why: a) constant velocity forward b) speeding up backward c) slowing down forward I understand that when the car's state of motion changes, in ...
*July 4, 2011*

**Nutrition**

How many grams of nitrogen are contained in a 2,500 kcal diet that provides 15% of the energy as protein? What would be the approximate weight gain of a person who consumes an excess of 500 kcal daily for one month? Which of the following is an FDA approved over-the-counter ...
*July 4, 2011*

**nutrition**

How many grams of nitrogen are contained in a 2,500 kcal diet that provides 15% of the energy as protein? What would be the approximate weight gain of a person who consumes an excess of 500 kcal daily for one month? Which of the following is an FDA approved over-the-counter ...
*July 2, 2011*

**Physics!**

I know I have to find angular speed in order to find the radius of orbit. With the radius of orbit and velocity I can find centripetal acceleration. I then apply Newton's 2nd Law to solve for the mass. I am stuck on finding angular speed...
*June 3, 2011*

**Physics!**

The two stars in a certain binary star system move in circular orbits. The first star, Alpha, has an orbital speed of 36 km/s. The second star, Beta, has an orbital speed of 12 km/s. The orbital period is 137 d. a) What is the mass of the star alpha? b) What is the mass of the...
*June 3, 2011*

**english**

Does anyone know how to write a universal theme paper?
*May 16, 2011*

**Physics HELP!**

You are at the controls of a particle accelerator, sending a beam of 3.90×10^7 m/s protons (mass m ) at a gas target of an unknown element. Your detector tells you that some protons bounce straight back after a collision with one of the nuclei of the unknown element. All...
*May 11, 2011*

**precalc**

I am really struggling with a bunch of problems. Any help with any of the following would be greatly appreciated. Thanks 1. ln e^(ln x) - ln(x - 3) = ln 8 2.3e^(6x - 2) = 18 The word problems, especially, are killing me. 3. In the formula A = Iekt, A is the amount of ...
*May 6, 2011*

**Math**

I know that I have to use log to solve, but I am having a hard time with the word problems. Please help Coffee is best enjoyed at a temperature of 121° F. A restaurant owner wants to discover the temperature T at which he should serve his coffee so that it will have ...
*May 6, 2011*

**physics**

If 7.00hp are required to drive a 1500-kg automobile at 66.0 km/h on a level road. What power is necessary to drive the car at 66.0 km/h down a 1.00 % grade? It requires 42.9 hp to drive the car at 66.0 km/h up a 10.0 % grade (a hill rising 10.0 m vertically in 100.0 m ...
*May 5, 2011*

**Physics**

It is a fact.
*May 4, 2011*

**Physics**

If 7.00hp are required to drive a 1500-kg automobile at 66.0 km/h on a level road. What power is necessary to drive the car at 66.0 km/h down a 1.00 % grade? It requires 42.9 hp to drive the car at 66.0 km/h up a 10.0 % grade (a hill rising 10.0 m vertically in 100.0 m ...
*May 4, 2011*

**math**

10.81 yrs for the first question 9 yrs for the second
*May 1, 2011*

**math**

So I think I have got these down I just really want to double check the answers to these two word questions. Thanks How long will it take for $9500 to grow to $36,300 at an interest rate of 12.4% if the interest is compounded continuously? Round the number of years to the ...
*May 1, 2011*

**MATH**

2, -4, 8,... The first term of the sequence above is 2, and every term after he first term is -2 times the preceding term. How many of the first 50 terms of this sequence are less than 100? (A) 22 (B) 25 (C) 28 (D) 30 (E) 37
*April 24, 2011*

**physics**

The 4.00-kg block in the figure is attached to a vertical rod by means of two strings. When the system rotates about the axis of the rod, the strings are extended towards the rod and each have a length of 1.25. The length from the upper string and lower string on the rod is 2...
*April 21, 2011*

**Chemistry**

If 40 g of KNO3 is dissolved in 100 mL of water at 25 degrees celisus, what will the final temperature be?
*April 17, 2011*

**Oral presentation**

ohh I see thank you for your help :)
*April 15, 2011*

**Oral presentation**

okay thanks! Its called "Not Marble, Nor the Gilded Monuments" by Shakespeare
*April 15, 2011*

**Oral presentation**

My teacher gave us a sonnet and he said that we have to do an oral presentation that faithfully interprets the meaning of the poem. Do you have any ideas on how to make an oral presentation describing a poem. Should I explain line by line or just put the sonnet in my own words...
*April 15, 2011*

**Physics**

A faulty model rocket moves in the xy-plane (the positive y-direction is vertically upward). The rocket's acceleration has components a(t)_x=alpha*t^2 and a(t)_y=beta-gamma*t, where alpha = 2.50 , beta= 9.00 , and gamma= 1.40 . At the rocket is at the origin and has ...
*April 13, 2011*

**math**

An initial investment of $1240 is appreciated for 17 years in an account that earns 8% interest, compounded continuously. Find the amount of money in the account at the end of the period.
*April 8, 2011*

**math**

The decay of 333 mg of a radioactive substance is given by A(t) = 333e-0.024t, where t is time in years. Find the amount left after 17 years.
*April 8, 2011*

**Physics**

If the expression for a given vector is Vector A-Vector B=(4-5)i^+(3+2)j^ and the magnitude of the difference of the vector is equal to 5.1. What is the direction of the difference Vector A - Vector B. (in the counterclockwise and +x direction)
*April 7, 2011*

**Physics**

Thank you!! That helped a lot
*April 7, 2011*

**Physics**

An explorer in the dense jungles of equatorial Africa leaves his hut. He takes 43 steps at an angle 45north of east, then 80 steps at an angle 60 north of west, then 51 steps due south. Assume his steps all have equal length. Save him from becoming hopelessly lost in the ...
*April 7, 2011*

**Physics (PLEASE HELP!)**

Two point charges, the first with a charge of +3.25×10−6 C and the second with a charge of -4.63×10−6 C , are separated by 25.5 cm. Find the magnitude of the electrostatic force experienced by the positive charge. Is the magnitude of the force ...
*April 4, 2011*

**Chemistry**

What is the concentration of OH- in a solution that contains 0.225g of NaOH in 0.250L of solution?
*April 2, 2011*

**Chemistry**

I am having trouble figuring out the calculations for osmotic pressure. This is what I need to do. Indicate whether the osmotic pressure of a 0.1M NaNO3 solution will be less than , the same as , or greater than that each of the following solutions a. 0.1M NaCl b. 0.1M KNO3 c...
*April 2, 2011*

**Biology**

in cattle a dominant gene (N) results in a deep notch in each ear. a recessive gene (n) results in an "udder" abnormiality when in the homozygous condition. a farmer desires to rid his herd of these characteristics. which of these two alleles would be easiest to ...
*March 25, 2011*

**Chemistry**

Enter the net ionic equation, including phases, for the reaction og AgNO3 (aq) with Ba(OH)2 (aq). I have Ag+ +OH- =AgOH but I dont know how to determine the phases.
*March 18, 2011*

**Math**

Miles said that he measured an angle of a regular polygon to be 130 degress. Explain why this result is impossible.
*March 17, 2011*

**Calculus**

a) Find a Cartesian equation relating and corresponding to the parametric equations: x=2sin(3t), y=9cos(3t). Write your answer in the form P(x,y)=0, where P(x,y) is a polynomial in x and y, such that the coefficient of y^2 is 4. b)Find the equation of the tangent line to the ...
*March 12, 2011*

**Calculus**

I just figured it out! thank you!
*March 12, 2011*

**Calculus**

if x=e^t and y=(t-3)^2 , find an equation y=mx+b of the tangent to the curve at (1,9).
*March 12, 2011*

**physics/physical science**

I have multiple questions like the following and need help on how to work out the answer of one because our book does not cover impulse. a car is at rest when it experiences a fwd propulsion force to set it in motion. it then experiences a second fwd propulsion force to speed ...
*March 2, 2011*

**physics**

a pirate ship fires a 25kg cannonball with a velocity of +100m/s at a very heavy fur trader ship. the ship is at rest. the cannonball bounces off the side of the ship, making a hole. after the collision the cannonball has a velocity of -0.5m/s. assume the water did not absorb ...
*February 28, 2011*

**World Civics**

How did the U.S. affect Latin America in the 1920's and 1930's? Was it positive or negative? Explain. What happened to Latin American governments in the 1930's? Why did it happen?
*February 25, 2011*

**Calculus**

A chain 27 feet long whose weight is 74 pounds is hanging over the edge of a tall building and does not touch the ground. How much work is required to lift the entire chain to the top of the building?
*February 11, 2011*

**calculus**

To find the slope of the tangent line you have to take the first derivative of f(x). So f'(x)=-5. Or you can also see that from the formula y=mx+b, where m is slope and b is your y intercept, that -5 is the slope. Because the original function is a line, the slope is the ...
*February 11, 2011*

**physics**

How much work is required to lift a 600-kg satellite to an altitude of 4 * 10^6 m above the surface of the earth? The gravitational force is F=GMm/r^2, where M is the mass of earth, m is the mass of the satellite, r is the distance between them. The radius of the earth is 6.4...
*February 11, 2011*

**Math**

Walking down a long moving escalator, Phil covered 75 m in distance in 25 seconds. Walking back up against the motion of the escalator, the distance was covered in 75 seconds. What was the speed of the escalator?
*February 6, 2011*

**statistics**

I have created my chart but am really confused on creating a Hypothesis and how to actually use the information obtained by my chart. The question is about the variance in a production process is an important measure of quality. A lrg var often signals an opportunity for ...
*January 28, 2011*

**english LAC 1**

28. Which of the following sentences contains a shift in tense? (Points : 5) Reading biographies helps you understand how the world works. Once he had finished the book, he will write the report. Sure, it is easy to dye clothes if you know how. The sky was clear and blue, and ...
*January 25, 2011*

**english LAC 1**

11. What kind of complement is the underlined word? Mom, give us a break, just once. (Points : 5) direct object indirect object predicate nominative predicate adjective 12. What kind of complement is the underlined word? Isn't this movie The Black Stallion? (Points : 5) ...
*January 25, 2011*

**math-finance**

Colin borrowed some money at 7.16%?a compounded quarterly. three years later. he paid $5000 toward the principal and the interest. after another two years, he paid another $5000. after another five years, he paid the remainder of the principal and the interest, which totalled...
*January 18, 2011*

**U.S.History**

Why was the Virginia Colony successful?
*January 9, 2011*

**Math**

yes, I think I found the second too. 6(x+1)(2x+1)?
*January 6, 2011*

**Math**

Find the second derivative of x(x+1)^3
*January 6, 2011*

**7th grade math**

6+x=2x-14. I'm not to sure how to solve this type of equation.
*January 6, 2011*

**Trigonometry**

Sketch a height versus time graph of the sinusoidal function that models each situation. draw at lease three cycles. assume that the first point plotted on each graph is at the lowest point: a girl lying on a an air mattress in a wave pool that is 3 m deep, with waves 0.5 m in...
*January 1, 2011*

**Math**

Suppose you invest $600 at an annual interest rate of 3.9% compounded continuously. How much will you have in the account after 25 years?
*December 24, 2010*

**Grade 11 math - HELP!**

Skyscrapers sway in high-wind conditions. in one case, at t=2s, the top floor swayed 30cm to the left (-30cm), and at t=12, the top floor swayed 30 cm to the right (+30cm) of its starting position. a) what is the equation of a sinusoidal function that describes the motion of ...
*December 21, 2010*

**Grade 11 math - HELP!**

Thank youu !
*December 12, 2010*

**Grade 11 math - HELP!**

The diameter of a car's tire is 52 cm. While the car is being driven, the tire picks up a nail. How high above the ground will the nail be after the car has travelled 0.1 km? can someone please explain how to solve this question?
*December 12, 2010*

**Math**

Thank you I found that at 0.213 of a cycle the distance travelled would be 34.8 cm in terms of the first cycle. And I found the height at that distance to be 22.15 cm Is that correct?
*December 12, 2010*

**Math**

The diameter of a car's tire is 52 cm. While the car is being driven, the tire picks up a nail. How high above the ground will the nail be after the car has travelled 0.1 km? It also asked me to graph this information. So I created a periodic graph that starts at 0 and ...
*December 12, 2010*

**Math**

Thank you so much!
*December 11, 2010*

**Math**

i don't think this is a cycloid because i'm only in grade 11 math and have never heard that term before this is from the "periodic function and their properties" unit so, is it possible to give me an answer related to that? thank you
*December 11, 2010*

**Math**

maria's bicycle has a diameter of 64 cm. as she rides at the speed of 21.6 km/h, she picks up a stone in her tire. draw a graph that shows the stone's height above the ground as she continues to ride at this speed for 2 s more. can someone please help me find the ...
*December 11, 2010*

**Chemistry**

What happens to the sample's reported water content if the salt decomposes yielding a volatile product? If the water is not completely removed from the salt during the heating process, will the reported water-to-salt mole ratio be high or low? Explain
*December 6, 2010*

**Chemistry**

If some volatile impurities in the crucible are removed from the hydrated MgSO4 along with the water, is the reported mass of water removed too high or too low. Explain.
*December 6, 2010*

**chemistry**

Enthalpy and Entropy in Reactions and Solutions Introduction In the course of most physical processes and chemical reactions there is a change in energy. In chemistry what is normally measured is H (enthalpy change), the change in heat at constant pressure and ignoring any ...
*November 30, 2010*

**phsyics**

The 3.0cm-diameter water line in the figure splits into two 1.0cm -diameter pipes. All pipes are circular and at the same elevation. At point A, the water speed is 2.0 m/s and the gauge pressure is 50 kPa. What is the gauge pressure at point B. I keep getting an answer that I ...
*November 15, 2010*

**Calculus**

Is it (0,0), (2,0) and (-2,0)?
*November 11, 2010*

**Calculus**

What are the coordinates of the points at which the slope of a function with the equation y=x^4-8x^2 is equal to zero? Please help me to understand how to approach this question.
*November 11, 2010*

**English**

"It" refers to gardening. Fransisco is telling his Grandpa that gardening is easy.
*November 8, 2010*

**tourism**

which aTourism gencies in Jamaica govern
*November 5, 2010*

**Chemistrty Help**

Calculate the wavelength of each of the following frequencies of electromagnetic radiation. 1040 kHz} (typical frequency for AM radio broadcasting) (assume four significant figures) in METERS? Can someone help me?
*October 29, 2010*

**Chem Help URGENT**

thank you so much
*October 28, 2010*

**Chem Help URGENT**

Could someone help me with these molecular formulas, i dont know what im doing wrong. For this example, i did it like this and it says its incorrect. Could you solve the the equations below your way and i match it to mines? Thank you so much Fe (s) + Ni(NO3)2 (aq) =Fe(NO3)2 (...
*October 28, 2010*

**history- political science**

Hi everyone =D thanks in advance to those who helped me. I am in need of a format or outline of some kind to help me write my 5-6 page term paper that is based on three books comparing and contrasting the themes within all three of their historic concerns on/of immigration ...
*October 23, 2010*

**American Government**

This is an old question, but for anyone cruising by looking for help, assuming we are using the same text book, you can refer to Chapter 3. The answer is pretty much right in front of you; you just have to write the paragraphs! Hope this helped. Good luck!
*October 22, 2010*

**Physics**

A rocket is fired at a speed of 75.0 m/s from ground level, at an angle of 63.0° above the horizontal. The rocket is fired toward an 11.0 m high wall, which is located 22.0 m away. By how much does the rocket clear the top of the wall?
*October 13, 2010*

**PHYSICS**

The blade of a windshield wiper moves through an angle of 90.0° in 0.49 s. The tip of the blade moves on the arc of a circle that has a radius of 0.6 m. What is the magnitude of the centripetal acceleration of the tip of the blade?
*October 5, 2010*

**PHYSICS**

A satellite is placed in orbit 6.30*10^5 m above the surface of the planet Jupiter. Jupiter has a mass of 1.90 1027 kg and a radius of 7.14*10.7 m. Find the orbital speed of the satellite.
*October 5, 2010*

**Math 3**

1700 3,500 1,600 7,400
*September 17, 2010*

**Math**

principle= rate x time p=rt $69.64=7.5% x t solve for t
*August 19, 2010*

**English/ Writing**

I have to persuade my teacher in an essay that a dog is an apple or that an apple is a dog. I can't think of any ways that a dog is like an apple and visa versa. Help!
*August 18, 2010*

**AP Biology**

^^ Thanks, Bobpursley.
*August 2, 2010*

**AP Biology**

It's alright... But could you at least mention that it's just a guess before you end up giving me a C+ in Biology..!
*August 2, 2010*

**AP Biology**

I am, but none of them are giving me the information I need. I researched them all for hours only to come out empty-handed.
*August 2, 2010*

**AP Biology**

You were wrong... It's not A.
*August 2, 2010*

**AP Biology**

Thanks, Ariyonia! :)
*August 2, 2010*

**AP Biology**

They type of learning that is involved in predator/prey interactions where an alteration in behavior is a response to stimulus is called A. Habituation Learning B. Cognitive learning C. Instinctive Learning D. Associative Learning E. Non-associative Learning I believe it can ...
*August 2, 2010*

**AP Biology**

What is not dependent on sunlight as a source of energy? A. Benthic Zone B. Pelagic Zone C. Neritic Zone D. Taiga E. Tundra I think it's A, B, or C. Is it?
*August 2, 2010*

**chemistry**

calculate the heat required to raise the temperature of 1.00 L of water from 17.0 degrees celcius to the boiling point
*July 13, 2010*

**Math**

The bases of a trapezoid are 24 and 33 inches long and it encloses an area of 571. Without determining the height of the trapezoid find the areas of the triangular regions into which the diagonals divide the quadrilateral?
*May 29, 2010*

**algebra**

An ostrich can run 174 feet in 3 seconds.
*May 27, 2010*

**algebra 2 / trig**

what is the square root of negative 150?
*May 24, 2010*

**WH**

Who traded coffee between 600-1450?
*April 28, 2010*

**English**

In the Great Gatsby, Why does Nick say that reserving judgements "is a matter of infinite hope?" in the opening chapter?
*April 27, 2010*

**French**

What word is NORCETMAIN unscrambled in French?
*April 14, 2010*

**city college**

discuss the cultural versus evolutionary explanations for gender differences in aggressiveness.
*April 10, 2010*