Thursday

February 11, 2016
Total # Posts: 643

**Physics**

When a block slides a certain distance down an incline the work done by gravity is 300 J. What is the work done by gravity if this block slides the same distance up the incline? a) 300 J b) zero c) -300 J d) It cannot be determined without knowing the distance the block ...
*March 25, 2007*

**Physics**

To streatch a certain nonlinear spring by an amount 2x requires a force F given by F=40x-6x^2 where F is in newtons and x is in meters. What is the change in potential energy when the spring is stretched 2 meters from its equilibrium position? a)16 J b)28 J c)56 J d)64 J e)80 ...
*March 25, 2007*

**Physics**

A target lies flat on the ground 3m from the side of a building which is 10m tall. A student rolls a ball off the horicontal roof of the building in the direction of the target. Air resistance is negligible. Te horizonal speed with which the ball must leave the roof if it is ...
*March 25, 2007*

**Physics**

The velocity of a projectile at launch has a horizontal component v_h and a vertical component V_V. Air resistence is negligible. When the projectile is at the hightest point of its trajectory, which of the following show the vertical and horizontal components of its velocity ...
*March 25, 2007*

**Physics**

An ideal massless spring is fixed to the wall at one end. A block of mass M attached to the other end of the spring oscillates with amplitude A on a frictionless, horizontal surface. The maximum speed of the block is V_m. The force constant of the spring is a)Mg/A b)MgV_m/2A c...
*March 25, 2007*

**Physics**

A spring has a force constant of 100N/m and an unstretched lenght of .07 m. One end is attached to a post taht is free to rotate in the center of a smooth table. The other end is attatched to a 1 kg disc moving in uniform circular motion on the table, which stretches the ...
*March 25, 2007*

**Physics**

A ball is tossed straight up from the surface of a small spherical asteroid with no atmosphere. The ball goes to a height ewual to the asteroid's radius and then falls straight down towardd the surface of the asteroid. What forces if any act on the ball while it is on the ...
*March 25, 2007*

**Physics**

The position of a toy locomotive mobing on a straight track along the x-axis is given the equation x=t^3-6t^2 +9t where x is in metters and t is in seconds. The net force on the locomotive is equal to zero when t is eqaul to a) zero b)2 s c)3 s d)4s e)5s Would the answer be b)...
*March 25, 2007*

**accounting**

if a bond sells at 102.5, what does that mean?
*March 20, 2007*

**Physics**

After a completely inelastic collision two objects of the same mass and the same initial speed are found to move away together at 1/2 thier initial speed. Find the angle bewteen the initial velocitie of the objects? Can you please show me the step to solve this problem? I am ...
*March 5, 2007*

**Physics**

A 50g mass (M1) will be attached to the trolley M2) and will cause it to accelerate a distance of between .5 to .6m. You also catch the trolley immediately after it has passed through the photogate. The time for the trip will be noted and recorded. The trolley is on a track. ...
*February 23, 2007*

**Of mice and men**

Would you say Steinbeck uses indirect or direct characterization of the characters? I think it's direct. For example he says, "The first man was small and quick, dark of face, with restless eyes and sharp features," (Steinbeck 2). I think you're right. That&#...
*February 19, 2007*

**math help**

Kim was charged $150.00 interest for 1 month on a $10,000 credit card balance. What was the monthly interest rate?
*February 8, 2007*

**Physics**

Trolley B will be at rest and trolley A will be given a push such that it collides with B, and they both move as one mass after the collision. As soon as the blocker of the picket fence on trolley A passes through the eye of the first photogate, trolley A must collide with ...
*February 6, 2007*

**Physics**

A railroad flatcar of weight W can roll without friction along astraight horizontal track. Initially, a man of weight w is standing on the car, which is moving to the right with speed v_0. What is the change in velocity of the car if the man runs to the left so that his speed ...
*February 5, 2007*

**area/length/volume**

the volume of the substance may Have a different weight. Such as a cup full of cottoncandy and a cupfull of rocks
*February 4, 2007*

**Physics**

A rocket whish is in deep space and initially at rest relative to an inertial reference frame, has a mass of 2.55 X 10^5 kg of which 1.81 X10^5 kg is fuel. The rocket engine is then fired for 250 s during which feul is consumed at the rate of 480 kg/s. The speed of the exhaust...
*February 2, 2007*

**Physics**

A 6090kg space probe mobing nose-first toward Jupiter at 105m/s relative to the Sun, fires its rocket engine ejecting 80 kg of exhaust at a speed of 253 m/s relative to the space probe. What is the final velocity of the probe? I should have gotten 108m/s Can yoou show me the ...
*February 2, 2007*

**math check please**

Find the median of the following set of numbers 45,21,54,22,65,61 Answer 49 1/2 2. find the mean and the median of the set of grades 95,75,76,86,96,71,68,81,95,76,69,82,93,88,94 Answer mean 83 median 82 3. find the mode of the following numbers 11,10,6,11,12 Answer 11 4. Find ...
*February 2, 2007*

**Physics... Please help me! I REALLY need help.**

A .30kg softball had a velocity of 15m/s at an angle of 35 degrees below the horizontal just before making contact with the bat. What is the magnitude of the change in momentum of the ball while it is in contact with the bat if the ball leaves the bat with a velocity of a)20m/...
*February 1, 2007*

**Speech**

A concluding strategy which helps to promote unity within a speech is a)a summary of main points b)a rhetorical question c)a refernce to the introduction D)a statistic The conclusion is supposed to tie the discoveries to the proposition in the introduction. So, I am suggesting...
*February 1, 2007*

**Physics**

A .30kg softball had a velocity of 15m/s at an angle of 35 degrees below the horizontal just before making contact with the bat. What is the magnitude of the change in momentum of the ball while it is in contact with the bat if the ball leaves the bat with a velocity of a)20m/...
*January 31, 2007*

**Science**

Does increasing the frequency of a wave also increase its wavelength? If not, how are these quantities related? high frequency. low wavelength That answer may be confusing. A high frequency has a short wavelength; i.e., 14 MHz is about 40 meters. 28 MHz is abouat 10 meters. 50...
*January 30, 2007*

**math help please**

(-3)^3-(-8)(-2)= -3 to the 3 power is -27 subtract -27 - -8 = -19 multiply by -2 =38 is this right please help (-3)^3-(-8)(-2) Use BODMAS rule So the answer is (-3)^3-16 ==>-27-16 =-43
*January 29, 2007*

**math check please**

region Population land area 1000mi^2 Asia 4,028,000,000 17,400 North America 305,000,000 9,400 1. Compare the populations per square mile in asia to the population per square mile in north america A: Asia 231.49mi^2 North America 32.45mi.^2 could some one please let me know if...
*January 24, 2007*

**Science**

A golf ball and a ping-pong ball are dropped in a vacuum chamber. When they have fallen halfway down, they have the same... A.speed B.potential energy C.kinetic energy D.Rest Energy my thought is that its c, kinetic energy...but i'm not 100% sure
*January 23, 2007*

**maths-- compound interest**

do you times the nt by the equation results to get the answer
*January 12, 2007*

**maths-- compound interest**

if investing 50,000 over 20 yrs at 3%apr with compouind interest figures semi-annually .figure using equation f(t)=p(1+r/n)nt
*January 12, 2007*

**Physical Science**

How much work is needed to raise a 110-kg load of bricks 12 m above the ground to being under construction? work in joules= weight*height where weight is mass*9.8m/s^2
*January 9, 2007*

**Math**

i see were u got that from but this 1 is confusing. 6 (index 3) square root of 36 times 2 (index 3)square root of 6 Please use the following for roots: sqrt cubroot etc. Those, with parenthesis, make the problem clear. 6 cube root of 36 times 2 cube root of 6 6 cubrt 36 + 2 ...
*January 7, 2007*

**Math**

Hi i was wondering what the square root of 3 times the squareroot of 9 is with little 3's on on the outside of the square roots for each of them ( the index) sqrt3 *(sqrt9)= 3sqrt3 Is that little 3 a cube root sign? If so, then a number to the 1/3 power is the same as the ...
*January 7, 2007*

**math help**

if a 150 lb person can burn 410 calories /hour while bicycling 12 mi/h What rate would a 120 lb person burn calories while bicycling 12 mi/h? can some one explain this to me how to solve these kind of problems One has to assume some relationship with caloric burning rate and ...
*January 7, 2007*

**math check**

1.find the area heigh 5ft width 8 ft A=H x W A= 5ft x 8Ft A= 40ft^2 2.The circular surface of a table has a diameter of 4 ft. What it will cost to have the top refinished if the company charges $5.00 per square foot for the refinishing ? Use 3.14 for pi and round your answer ...
*January 6, 2007*

**Biology**

DNA was collected from 100 people and subjected to a restriction digest with BamHI. These samples were then analyzed using Stouthern blots. Three different patterns of hybridization were seen on the blots: 56 samples showed a single band of 6.3kb, 6 samples showed a single ...
*December 6, 2006*

**Biology**

if the incidence of cystic fibrosis is 1 in 2500, what is the expected frequency of carriers for the CF allels? assume that this population is in Hardy-Weinberg equilibrium. I appreciate a hint to start this answering this problem. p^2 + 2pq + q^2 = 1 p + q = 1 q^2 is the ...
*December 6, 2006*

**biology**

Can someone explain how the DNA vaccine differ from a traditional vaccine? Since this is not my area of expertise, I searched Google under the key words "DNA vaccine" to get these possible sources: http://people.ku.edu/~jbrown/dnavac.htm http://en.wikipedia.org/wiki/...
*December 5, 2006*

**biology**

Can someone explain how the DNA vaccine differ from a traditional vaccine?
*December 5, 2006*

**biology**

Why are enzymes needed by the cell? en.wikipedia. org/wiki/Enzyme
*December 5, 2006*

**Identifying controls and Variables**

Krusty was told that a certain itching powder was the newest best thing on the market, it even claims to cause 50% longer lasting itches.Interested in this product, he buys the itching powder and compares it to his usual product.One test subject (A) IS SPRINKLED WITH THE ...
*October 1, 2006*

**science**

pixelgolomcg
*September 28, 2006*

**cell biology**

Motor proteins such as as kinesin and dynein move along the cytoskeleton using the energy generataed from the hydrogen________, this phosphorylated nucleotide. a. GDP B. GTP C. ATP D. ADP i THINK THE RIGHT ANSWER IS "C" PLEASE CHECK Since this is not my area of ...
*August 1, 2006*

**bio**

1. DAG activates _______.In turn kinase_____ its own substrate a. PKA, phosphatates b. PKA, phosphorylates c. PKC, phosphates d. PKC,phosphorylates I think the right answer is d, please check Since this is not my area of expertise, I searched Google under the key words "...
*August 1, 2006*

**Cell Bio**

Sometimes, certain enzymes are associated with a particular organelle of the cell. Many times scientists have had to use ________________ centrifugation to separate different constituents of the cell. Following this procedure, you aliquot the fractions into separate test tubes...
*June 17, 2006*