Science & Mathematics - 27 October 2006

There is a gun in which the barrel length is 62cm and has a muzzle velocity of 450m/s. A wooden chair of 30 kg sits on a wooden floor. A bullet of 10g penetrates the chair and the bullet lodges itself into the chair 9 centimeters. How far back, in centimeters, did the chair fly back? The coefficient of kinetic friction between the chair and the floor is 0.2

I'm not really sure how to approach this problem other than trying to use momentum conservation but do I need to find the force of the bullet on the chair to find the acceleration and then use momentum conservation to find the velocity, but i don't think that works. Any direction please?

2006-10-27 08:59:48 · 3 answers · asked by Bryan C 2 in Physics

2006-10-27 08:59:11 · 9 answers · asked by totallyclueless 1 in Biology

2006-10-27 08:58:01 · 2 answers · asked by totallyclueless 1 in Biology

2006-10-27 08:57:21 · 8 answers · asked by Anonymous in Zoology

I was just wondering if any over-the-counter medications have antibiotics in them...or does all of them have them to fight off infections? Which one do you think would be the strongest?

2006-10-27 08:57:01 · 9 answers · asked by mysterious_qt 2 in Medicine

2006-10-27 08:56:08 · 5 answers · asked by totallyclueless 1 in Biology

can a simple nail electromagnet repel (or push anythng away from it.

2006-10-27 08:55:06 · 3 answers · asked by Randi L 1 in Other - Science

2006-10-27 08:54:19 · 9 answers · asked by Christi B 1 in Mathematics

2006-10-27 08:53:35 · 10 answers · asked by andrewil07 1 in Chemistry

2006-10-27 08:53:33 · 3 answers · asked by Anonymous in Engineering

I'm moving to NYC from LA. So you can imagine the drastic change I'm getting ready to experience. Can someone please give a month to month synopsis of the weather. I can only find current weather information online, and would like to know how to plan for a typical year. Thanks!

2006-10-27 08:50:24 · 5 answers · asked by Shoe Gyrl 2 in Weather

... does that mean it is at least 27.4 Billion lightyears in diameter?
And, if we can see back 13 Billion years, how come it took this long for light from then to arrive, when at the time the size of the universe would at most have been 1.5 Billion light years?

2006-10-27 08:48:48 · 10 answers · asked by Anonymous in Astronomy & Space

I'm looking for the english names and description of the different parts of a postmill.
For example : post, canister, windboard ...

2006-10-27 08:45:34 · 4 answers · asked by sylvie p 1 in Engineering

dont know what is this .anybody know the formula pls help

2006-10-27 08:42:50 · 3 answers · asked by rimple 1 in Mathematics

2006-10-27 08:41:36 · 18 answers · asked by leothescouser 1 in Biology

2006-10-27 08:39:40 · 7 answers · asked by Anonymous in Zoology

2006-10-27 08:39:04 · 8 answers · asked by yazmin o 1 in Zoology

account at the end of 3 years?
I came up with $3360.00 am I correct?

2006-10-27 08:37:26 · 3 answers · asked by momoftwins1986 1 in Other - Science

2006-10-27 08:34:24 · 6 answers · asked by Anonymous in Astronomy & Space

What is efficiency measured in? Low resolution suggests the column is efficient - how low is low?

2006-10-27 08:34:24 · 2 answers · asked by the forensics kid 1 in Chemistry

2006-10-27 08:31:48 · 8 answers · asked by Vijay 1 in Astronomy & Space

2006-10-27 08:30:14 · 7 answers · asked by tdavis570 1 in Chemistry

I have a nuclear energy project for physics othe groups have wind and solar they are creating a windmill and generating electricity using cabon wires. I NEED SOME IDEAS FOR NUCLEAR ENERGY BEST IDEA GETS 10 POINTS..

2006-10-27 08:27:17 · 3 answers · asked by shivansh_r_sharma 1 in Engineering

2006-10-27 08:20:29 · 3 answers · asked by bucky 1 in Biology

yo, i heard that sperm whales release loads of their sperm into the ocean while having sex....only a certain small amount of the whale sperm goes into his partner...

is this true? and how many gallons of sperm is released in the ocean during sex intercourse??

thanks!!!!!!!!!!!!!!!!!!!!!!!

2006-10-27 08:20:16 · 4 answers · asked by d29061 2 in Biology

In cats, yellow fur (B) is dominant to balkc fur (b), and the gene is located on the X chromosome. The heterozygous "tortoise-shell" or "calico" condition is exhibited only by the female, and is a reuslt of mosaic expression. What offspring (genotypes, phenotypes & frequencies) would you expect from the cross of a black male with a yellow female?

2006-10-27 08:19:57 · 5 answers · asked by Anonymous in Biology

If I am asked to graph the function of V = 3-0.05cos(200*phi*t) in a graphing calculator of one period, what should I set my window range to? Thanks

How about for 10*phi* sin(200phi*t)?

2006-10-27 08:18:27 · 3 answers · asked by Anonymous in Mathematics

Bill and Bob both drive 60 miles to work. By averaging 10 miles per hour faster than Bob, Bill gets to work 12 minutes earlier than Bob. How fast does each one drive?

2006-10-27 08:15:33 · 4 answers · asked by sillyboys_trucksare4girls 2 in Mathematics

2006-10-27 08:12:54 · 10 answers · asked by irockyourwrld 1 in Other - Science

2006-10-27 08:11:44 · 7 answers · asked by Anonymous in Chemistry