Science & Mathematics - 28 November 2007

A 0.446-kg puck, initially at rest on a frictionless horizontal surface, is struck by a 0.313-kg puck that is intitially moving along the x-axis with a velocity of 3.18 m/s. After the collision, the 0.313-kg puck has a speed of 2.18 m/s at an angle of 37 degrees to the positive x-axis.

(a) Determine the velocity of the 0.446-kg puck after the collision.

(b) Find the fraction of the kinetic energy lost in the collision

i got 1.44 m/s as the velocity but that answer is wrong i dont know what i did wrong

2007-11-28 13:29:02 · 1 answers · asked by njbadboy4life2005 3 in Physics

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Number Theory?

Try this out =D!

Given that D_n + D_(n-1) + ... + D_2 + D_1 mod 3 = 0

Prove that:
D_n * 10^(n-1) + D_(n-1) * 10^(n-2) + ... + D_2 * 10 + D_1 is divisble by 3 also.

2007-11-28 13:27:48 · 4 answers · asked by UnknownD 6 in Mathematics

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I belive my plutonium is oxidizing?

I belive my plutonium is oxidizing. what should i do?

2007-11-28 13:25:26 · 11 answers · asked by Sam 3 in Chemistry

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How large is the sun compared to earth?

2007-11-28 13:24:09 · 6 answers · asked by blah 1 in Astronomy & Space

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Math help please :) Thank You!!! CALCULUS?

The derivative of a power formula was derived for integer exponents, but works for any rational constant exponent. Demonstrate that this is true for y=x^(13/7) by first transforming the equation so that it involves only integer exponents, then differentiating implicitly with respect to x

2007-11-28 13:23:53 · 2 answers · asked by imagination_inevitable 1 in Mathematics

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Graphing Fx=kx (hooke's law) why is Fx on the y-axis when clearly it is the independent variable.?

Fx=kx
Fx is force applied to Spring
k is constant (N/m)
x is change in length of the spring

2007-11-28 13:21:23 · 2 answers · asked by lozter 1 in Physics

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name 6 rivers that feed into mississippi river?

2007-11-28 13:20:32 · 2 answers · asked by CRAZYCHICKEN 1 in Geography

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help me in physics homework please???

an object is hit, giving it an initial velocity of 4 m/s. If the coefficient of kinetic friction between the ice and puck is 0.05, how far will the puck slide before stopping?
***please show free body diagrams and equations used, thanks!!!!!

2007-11-28 13:20:20 · 1 answers · asked by cooldude123 2 in Physics

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can someone help me solving this problem: 1/2(8n+12)-27=15?

2007-11-28 13:18:25 · 6 answers · asked by funnybonez93 2 in Mathematics

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What is is the Sun made up of (Main gases)?

2007-11-28 13:18:00 · 3 answers · asked by blah 1 in Astronomy & Space

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Math Help?

Solve inequality.

-10.7 > x/-4

x/1.3 > 7.1

-3.8x > 28.5

2007-11-28 13:14:57 · 5 answers · asked by Anonymous in Mathematics

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What is the y-intercept of the graph of the function y= -(x-4)squared-25?

2007-11-28 13:12:41 · 7 answers · asked by Chuck B 2 in Mathematics

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prime numbers?

ok can someone please tell me the prime numbers between 1 and 30 this was on a test and i think i did it right but she marked it wrong..

2007-11-28 13:12:31 · 8 answers · asked by blue_Eyes03 2 in Mathematics

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(12x) (12x + 11)?

im having some trouble i think the answer is 144x+11 but i'm not sure if i'm right

2007-11-28 13:10:58 · 8 answers · asked by me 2 in Mathematics

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A player hits a home run, and the base ball clears a wall 8 meters high located 113.6 m away from home plate.?

The ball is hit at an angle of 38.7 degrees to the horizontal, and air resistance is negligible. Assume the ball is hit at a height of 1.2m above ground.
what is the initial speed of the ball? (m/s)
How much time does it take for the ball to reach the wall? (s)
Find speed of ball when it reaches the wall. (m/s)

2007-11-28 13:10:43 · 1 answers · asked by Anonymous in Physics

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PLEASE help with this Calculus problem?

Consider the curve defined by -8x^2+5xy+y^3=(-)149
a) Find dy/dx
b) Write an equation for the line tangent to the curve at (4,-1)
c) There is a number k so that the point (4.2, k) is on the curve. Using the tangent line found in part (b), approximate the value of k.
d) Write an equation that can be solved to find the actual value for k so that the point (4.2, k) is on the curve.
e) Solve the equation found in part (d) for the value of k.

I'm pretty sure i got parts a and b..... but need major help w/ the rest.....

2007-11-28 13:10:01 · 2 answers · asked by otsoccerplaya 2 in Mathematics

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bottle with some sort of pipe and filled with water?

There's this soda bottle. There's some sort of pipe or tube of some sort sticking out. There is a funnel at the top of the bottle. When you pour half a beaker full of water into the soda bottle, the pipe pours out more water than what was put into it (it filled two beakers and half a basin I think). Why is that?
Hints: the soda bottle already has water in it, the tube is longer than the soda bottle, (so it's got to be curved or something) there's no valve, there's something in the bottle (but I think it's just the tube and water)

Please help. I've been dying to know what's making the bottle do this since my science teacher showed a demonstration.

2007-11-28 13:09:46 · 9 answers · asked by janna 2 in Other - Science

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Physics: Car Collision at an Angle, Trying to figure out, Please help!?

Two cars, both of mass m, collide and stick together. Prior to the collision, one car had been traveling north at speed 2v, while the second was traveling at speed v at an angle phi south of east (as indicated in the figure). After the collision, the two-car system travels at speed v_final at an angle theta east of north.

What is the angle theta with respect to north made by the velocity vector of the two cars after the collision?

Express your answer in terms of phi. Your answer should contain an inverse trigonometric function.

I was trying to solve it by breaking it down the components in x & y direction.

so i did in x-direction: (2m)v_i cos (0) - (2m) 2v_i sin (theta) = (2m)v_i tan (theta)

Now i used the formula m1v1+m2v2= (m1+m2)v3

Since this is inelastic i thought the 2nd direction would be subtracted since energy isn't conserved.

Please help i tried to do the algebra and im confused. Am i even supposed to be using this equation?

2007-11-28 13:09:05 · 4 answers · asked by Anonymous in Mathematics

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Physics: Car Collision at an Angle, Trying to figure out, Please help!?

Two cars, both of mass m, collide and stick together. Prior to the collision, one car had been traveling north at speed 2v, while the second was traveling at speed v at an angle phi south of east (as indicated in the figure). After the collision, the two-car system travels at speed v_final at an angle theta east of north.

What is the angle theta with respect to north made by the velocity vector of the two cars after the collision?

Express your answer in terms of phi. Your answer should contain an inverse trigonometric function.

I was trying to solve it by breaking it down the components in x & y direction.

so i did in x-direction: (2m)v_i cos (0) - (2m) 2v_i sin (theta) = (2m)v_i tan (theta)

Now i used the formula m1v1+m2v2= (m1+m2)v3

Since this is inelastic i thought the 2nd direction would be subtracted since energy isn't conserved.

Please help i tried to do the algebra and im confused. Am i even supposed to be using this equation?

2007-11-28 13:08:47 · 4 answers · asked by Anonymous in Physics

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