Science & Mathematics - 6 November 2007

Why isn't the problem of diving by 0 addressed in a similar way?

2007-11-06 09:24:26 · 6 answers · asked by I'm an Atheist 3 in Mathematics

I built a small dc motor for a class using an electromagnet and two AA batteries. The requirements limit me to only using (2) 1.5V batteries. I read that I can increase the torque by either increasing the magnetic field or increase the current. My goal is to lift as much as possible with it, and I am on a limited budget, so the increase in current sounds more desirable I think. Please help!

2007-11-06 09:24:10 · 5 answers · asked by DC Motor Project 1 in Engineering

A small WWI biplane traveling at 120 km/hr in a straight and level flight 160 meters above the ground drops a small contact bomb. Find:

(a) the time it takes for the bomb to fall to the ground
(b) the horizontal distance traveled by the bomb after is it released
(c) the vertical speed acquired by the bomb as it just touches the ground
(d) the total speed of impact

2007-11-06 09:22:51 · 2 answers · asked by labelapark 6 in Physics

Question 1 - Please explain in steps if possible

A bicycle wheel is 30 inches in diameter.
a. To the nearest revolution, how many times will the wheel turn if the bicycle is ridden for 3 miles?
b. Suppose the wheel turns at a constant rate of 2.75 revolutions per second. What is the linear speed in miles per hour of a point on the tire?

Question 2

Low Earth orbiting (LEO) satellites orbit between 200 and 500 miles above Earth. In order to keep the satellites at a constant distance from Earth, they must maintain a speed of 17,000 miles per hour. Assume Earth's radius is 3960 miles.

a. Find the angular velocity needed to maintain a LEO satellite at 200 miles above Earth.
b. How far above Earth is a LEO with angular velocity of 4 radians per hour?
c. Describe the angular velocity of any LEO satellite.

2007-11-06 09:20:06 · 1 answers · asked by Anonymous in Physics

Find the following using the given coordinates on the number line:

The distance between -128 and 35

The midpoint of the segment with endpoints -29 and 97.

If anyone could help, it'd be greatly appreciated. Thanks!

2007-11-06 09:19:41 · 3 answers · asked by Yahoo! King 1 in Mathematics

(4.3) (3.59)

2007-11-06 09:19:37 · 4 answers · asked by My Life is in Black and White 4 in Mathematics

2007-11-06 09:19:34 · 3 answers · asked by Chess 2 in Mathematics

need to know how to refine math parabola intersections

2007-11-06 09:19:22 · 1 answers · asked by Craig S 2 in Mathematics

2007-11-06 09:18:51 · 1 answers · asked by Anonymous in Chemistry

on a plane, there is a line and a point not on the line. how many lines can be drawn through it that are parallel to the first line?

what about on a sphere?

and how do alternate angles and corresponding angles hold for spherical geometry?

2007-11-06 09:18:12 · 2 answers · asked by Anonymous in Mathematics

This is in chemistry and we have been doing all sorts of molality equations and so forth and have just been given this and not quite sure i follow.

We are asked in question 4:

Part A
What are the six types of radioactive decay?
I found that they were...
α emission, (alpha)
β emission (beta)
γ emission (gamma)
positron emission
electron capture
spontaneous fission


But then it asks in part B of the question...

Complete the following nuclear equations
a. proton -> neutron + ?
b. neutron -> proton + ?
c. proton + ? -> neutron

am i supposed to use one of the following types of radioactive decay? thanks for the help and assistance!

2007-11-06 09:18:04 · 3 answers · asked by john s 3 in Chemistry

describe all the ways in which two distinct great cricles can intersect on the sphere. can two great circles ever be parallel?

if i great circle is on a sphere, what figure can be drawn that is always the same distance from the great circle, can it be a great circle?

2007-11-06 09:15:02 · 3 answers · asked by Anonymous in Mathematics

is there a name for that theory and how did he fugure i out? many thanks

2007-11-06 09:14:04 · 11 answers · asked by Anonymous in Astronomy & Space

imagine that it is possible for a pair of railroad tracks to extend all the way around the earth. can they be parallel?

2007-11-06 09:11:25 · 4 answers · asked by Anonymous in Engineering

2007-11-06 09:11:19 · 4 answers · asked by Anonymous in Engineering

Everyone's answer to what happens if you fall into a black hole is that you would get killed by being squished (by tidal forces). But it seems that everyone fails to keep in mind the relativistic effect that gravity has on time. Since time for the person falling will slow when they enter the stronger gravitational field, my idea is that the person will starve to death long before they actually get squished. Hows my logic?
For those of you who cant refrain from telling me that I will get squished no matter what, then answer this follow up question. Assume a hydrogen atom falls into the black hole, how many revolutions will its electron make before the atom becomes part of the black hole core? Compare this to a hydrogen atom that has not fallen into the black hole.

2007-11-06 09:09:26 · 11 answers · asked by Nick D 2 in Astronomy & Space

2007-11-06 09:09:06 · 2 answers · asked by jim m 5 in Astronomy & Space

2007-11-06 09:08:11 · 16 answers · asked by 127.0.0.1 2 in Mathematics

to stay in it's place.


why?

2007-11-06 09:04:38 · 1 answers · asked by Anonymous in Physics

is it worse, the same of better? assume that other factors such as speed and tires are the same

please explain, i'm totally lost!

2007-11-06 09:03:50 · 2 answers · asked by Anonymous in Physics

2007-11-06 09:01:16 · 4 answers · asked by tommiejbrothers 1 in Astronomy & Space

The rod is 4m long, with a weight Fg. One end, Point B, is supported by a cable from the wall. The other end, Point A, rests against a wall with μ s = 0.5. The angle between the cable and Point B is 37 degrees. Basically, the question is asking how far out from the wall can an extra weight, Fg, same as the weight of the rod, be placed without causing the rod to slip at Point A. (Diagram looks smiliar to a triangle). No actual weights are given.

2007-11-06 09:01:04 · 1 answers · asked by Anonymous in Physics

A ferrari accelerates from 0 to 100 km/h in 4.8 sec. What force (in newtons) does a passenger of mass 68 kg experience during acceleration?

2007-11-06 09:00:53 · 2 answers · asked by Paul T 1 in Physics

just wondering for fun?

2007-11-06 08:59:52 · 17 answers · asked by Anonymous in Mathematics

If you have 2 days how mant minutes are in both days all together?

2007-11-06 08:58:44 · 5 answers · asked by Anonymous in Mathematics

What is the efficiancy?

Please show me how to do it. I was absent and my teacher precisely doesn't teach us how to do anything.

I know Efficiency = (W out / W in) * 100% but how do you get W out and W in? :O

2007-11-06 08:58:08 · 1 answers · asked by xuchihasakurax 2 in Physics

Some carbohydrates are related to other substances that aren't carbohydrates in nature enumerate?

this is a question from my biochem. doctor. i tried doing it but no idea. Please guide me if possible with DETAILS PLEASE.


Thanks in advance

2007-11-06 08:57:53 · 2 answers · asked by Anonymous in Chemistry

When the sun is 62 degrees above the horizon, a building casts a shadow 18 m long. How tall is the building?

If you cant at least tell me how to set it up, it would be great.
THANK YOU!

2007-11-06 08:54:24 · 2 answers · asked by lonelioness 4 in Mathematics

A 50.0 kg archer, standing on frictionless ice, shoots a 200 g arrow at a speed of 200 m/s. What is the recoil speed of the archer?

2007-11-06 08:51:02 · 1 answers · asked by Paul T 1 in Physics

I was wondering if drinking caffeinated befferages on the day of a blood pressure test will have any affect. It's not a serious test, but I've heard of caffeine raising blood pressure over time and I'm not sure if drinking it will have any immediate affect on the results. Any help?

2007-11-06 08:50:54 · 4 answers · asked by Anonymous in Medicine