Science & Mathematics - 30 November 2007

A mini-golf course has a windmill that blocks the opening lower level of the course. The windmill has 4, 2 m long blades that are 25 cm wide at the ground and complete 2 revolutions per minute. If the ball starts from rest 10 meters away, what is the minimum speed with which you must strike the ball on level ground in order to have it pass between the blades?

2007-11-30 08:21:48 · 1 answers · asked by Anonymous in Physics

2007-11-30 08:21:22 · 1 answers · asked by Alexander 6 in Mathematics

are possible?

2007-11-30 08:20:28 · 2 answers · asked by DuckyWucky 3 in Mathematics

Is it possible to make virtual simulation glasses like the ones posted at the link below. http://www.youtube.com/watch?v=TNUfefCGMwE (Time - 1:30) Is possible to create such an immersive experinece using just glasses? I've seen that scene in the movie and he's sorounded by 4 compuetr colums but could it work without them just make them a big as cyclops's visor maybe. Whoever is reading this question and has theory on how this might work PLEASE ANSWER.

2007-11-30 08:17:19 · 1 answers · asked by Anonymous in Engineering

For sum(Cn*x^n)

I'm supposed to enter in c3-c7
I already know that c4 and c6 are 0 because the derivative is something*sin(0)=0

but for the odd numbered c's I am having problems...
i know that the taylor series for sinx = sum( (-1^n) * x^(2n+1) )/ (2n+1)!
so i just substituted in 5x and multiplied by 5x^2 and got
5sum( (-1^n) * ( 5^(2n+1) * x^(2n+3) ) / (2n+1)!

so for c3 i got 5(-1^3)(5^7)/(7)! = -5^8/7!
but I am not getting the answer right for this. Can someone please explain what I am doing wrong.

2007-11-30 08:17:11 · 4 answers · asked by mula 2 in Mathematics

I don't know where to start from? Pls help if you know
Thanks!
Here is the problem:

Trying to beat the heat of the last summer, a physics student went to the local toy store and purchased a plastic child's swimming pool. Upon returning home, she filled it with 200 liters of water at 25oC. Realizing that the water would probably not be cool enough, she threw ice cubes from her refrigerator, each of mass 30g, into the pool. (The ice cubes were originally at 0oC.) She continued to add ice cubes, until the temperature stabilized to 16oC. She then got in the pool.
The density of water is 1000 kg/m3, the specific heat of water is 1.0 cal/g C, the specific heat of ice is 0.5 cal/g C, and the latent heat of fusion of water is 80 cal/g.


How many ice cubes did she add to the pool to get the temperature to 16 C? (Consider the pool and ice cubes an isolated system.)

2007-11-30 08:15:52 · 1 answers · asked by alra 2 in Physics

I used to do some astronomy with a 4.5" newtonian refracting telescope but the size of the aperture was not great enough to see some objects with the clarity that I would have liked...

That said, I would like to spend between $1000-2000 on a good telescope for astronomy purposes. I REALLY want to do some photography and have a telescope with the motors that lock-on to the celestial coordinates of the object and "goto" functions.

My question is:

What telescope manufacturer do you recommend, what specific telescopes, and what type of imagers?

Thanks!!

2007-11-30 08:11:13 · 9 answers · asked by Ben H 5 in Astronomy & Space

http://www.ethicalsuperstore.com/products/h20/h20-8-digit-waterpowered-calculator-with-replacable-cell/

2007-11-30 08:10:44 · 4 answers · asked by Timothy H 3 in Other - Science

Feel free to also explain how we know that carbon decays at a constant rate, especially now that we know that the speed of light is not a constant.

2007-11-30 08:10:02 · 5 answers · asked by MrMyers 5 in Other - Science

Can someone help me on simplifying the square root of 2x/3. I think its 3 times the sqrt x over 2. But i really think Im wrong on this one

2007-11-30 08:07:47 · 4 answers · asked by ~*~ victoria ~*~ 1 in Mathematics

they both make you sick.

i have a test soon and i need to no this! iv been studing hard...but i dont get it

oh im in 10th grade...keep the answers somewhat understandible =]
thanks

2007-11-30 08:07:38 · 7 answers · asked by haleyalley 2 in Biology

I had to do Physics at college, and i'm struggling with my homework! Can anyone please help me and not just give me the answer- but explain how to do it so in future I can do it. Thankyou!

Large metal bars can be driven into the ground using a heavy falling object. The object (driving the bar into the ground) has a mass 2.0x10^3 kg and the metal bar has a mass of 400kg. The object strikes the bar at 6.0ms/-1. It comes to rest on the bar without bouncing. As a result of the collision, the bar is driven into the ground to a depth of 0.75 m.
(worth 4 marks)

(a) Determine the speed of the bar immediately after the object strikes it.
(3 marks)

(b) Determine the average frictional force exerted by the ground on the floor.

2007-11-30 08:03:09 · 2 answers · asked by Anonymous in Physics

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2007-11-30 08:02:01 · 9 answers · asked by Alexander 6 in Mathematics

do people really saw alians

2007-11-30 08:01:12 · 5 answers · asked by Vy P 2 in Astronomy & Space

They're beside each other so, ya know. Comparison and all that.

Thanks.

2007-11-30 08:00:52 · 3 answers · asked by Jansen J 4 in Astronomy & Space

The value of z is calculated from the following formula:
z=(12a+5b)/(11a+19b)

a is increased by 2.2%
b is increased by 1.2% of a
Using partial differentiation, find an expression for the percentage change in z in terms of a and b.
b is measured as 11.
What non-zero value of a would result in a zero percentage change in z?

2007-11-30 07:56:25 · 1 answers · asked by ozi 1 in Engineering

The value of z is calculated from the following formula:
z=(12a+5b)/(11a+19b)

a is increased by 2.2%
b is increased by 1.2% of a
Using partial differentiation, find an expression for the percentage change in z in terms of a and b.
b is measured as 11.
What non-zero value of a would result in a zero percentage change in z?

2007-11-30 07:56:10 · 3 answers · asked by ozi 1 in Mathematics

Here we are on a planet that spins around the sun, a sun that spins around the galaxy and galaxy that spins around the local group.

How long would you have to be a couch potato sitting with your can of beer and your remote control in order to travel one light year?

You can use Newtonian or Einsteinian mechanics, or your own imagination.

2007-11-30 07:55:43 · 7 answers · asked by Frst Grade Rocks! Ω 7 in Astronomy & Space

Thanks for any help provided!

2007-11-30 07:54:27 · 2 answers · asked by Sirius Blanca 1 in Other - Science

Me and my friends were wondering about it and discussing it...

Logical answers only please.

2007-11-30 07:49:55 · 18 answers · asked by Missweetiepie94 1 in Astronomy & Space

What is the total number of humans that have ever walked the earth? Estimated

2007-11-30 07:45:36 · 3 answers · asked by Tim Sing 1 in Earth Sciences & Geology

I came upon this in trying to solve for molar mass in a problem. The Ideal gas law was re-arranged to molar mass=dRT/P. or P=mass/molar mass x RT/V Where mass/V=d. I just dont understand how n=mass/molar mass.

2007-11-30 07:44:45 · 7 answers · asked by James K 1 in Chemistry

My friends and I have been debating if the world is going to end on December 21st, 2012? Will it or not?

2007-11-30 07:44:24 · 12 answers · asked by Maddie.Klonsinski 2 in Astronomy & Space

Consider a 8.89-kg mass on the end of a linear spring in simple harmonic motion. The spring has spring constant 4.31 N/m. When the spring is maximally extended, it is 0.0156 m from the place in the oscillation where it is maximally compressed. The equilibrium position of the spring is midway between these two extremes. What is the mechanical energy of the mass in this oscillation? (Answer in J.)

2007-11-30 07:43:37 · 1 answers · asked by josh j 1 in Physics

2007-11-30 07:43:02 · 3 answers · asked by Anonymous in Weather

A 0.390 kg green bead slides on a curved frictionless wire, starting from rest at point A in Figure P6.52. At point B the bead collides elastically with a 0.600 kg blue ball at rest. Find the maximum height the blue ball rises as it moves up the wire. In m please! the figure is on this page: http://www.webassign.net/sercp/p6-52.gif

2007-11-30 07:41:30 · 1 answers · asked by Dave 1 in Physics

Evaluate the function at the specified value f(x)= -x^3+5x^2-7x-8



A. find f(-3)
b. find f(0)
c. find f(2)

2007-11-30 07:37:49 · 9 answers · asked by Anonymous in Mathematics

A 10.0 g object moving to the right at 21.0 cm/s makes an elastic head-on collision with a 15.0 g object moving in the opposite direction at 31.0 cm/s. Find the velocity of each object after the collision. I need to find the velocity of the 10 g object and 15 g object.. in cm/s.. thanks!!

2007-11-30 07:37:08 · 3 answers · asked by Dave 1 in Physics

(5/8)/(15/16)

2007-11-30 07:33:39 · 8 answers · asked by Jayden K 1 in Mathematics

2007-11-30 07:29:46 · 13 answers · asked by lockkd_ll 1 in Mathematics