Science & Mathematics - 9 February 2007

A driver in a car traveling at a speed of 60 mi/h sees a deer 80 m away on the road. Calculate the minimum constant acceleration that is necessary for the car to stop without hitting the deer (assuming that the deer does not move in the meantime).

2007-02-09 05:57:09 · 5 answers · asked by Erin C 1 in Mathematics

And how I will put in these batteries. There is a cover at the back which looks impossible to take off.

2007-02-09 05:56:28 · 3 answers · asked by Anthony F 6 in Engineering

2007-02-09 05:55:45 · 15 answers · asked by tatolok 1 in Mathematics

Could you show me the solving process to get to the answer as well as help me get the answer?

2007-02-09 05:53:16 · 2 answers · asked by Anonymous in Chemistry

I have a project to do where I must build a car without pushing it to start. I can wind, blow, etc. on something that will make the car go. The only thing not allowed is pushing the actual car with my hand. Any ideas?

2007-02-09 05:53:05 · 4 answers · asked by Victoria 1 in Engineering

2007-02-09 05:50:22 · 6 answers · asked by sam 1 in Weather

Did I do this right? It seems to easy.

The last 40 violent crimes committed in Sconeville were 2 homicides, 25 robberies, and 13 assaults. What is the empirical probability that the next violent crime committed in Sconeville will be a robbery?

Frequency
Homicides – 2
Robberies – 25
Assaults – 13

Total = 40

The probability is 25/40 or .6250

2007-02-09 05:50:09 · 3 answers · asked by Anonymous in Mathematics

2007-02-09 05:48:12 · 1 answers · asked by Anonymous in Botany

2007-02-09 05:47:56 · 5 answers · asked by california1991qt 1 in Zoology

A truck on a straight road starts from rest and accelerates at 2.0 m/s2 until it reaches a speed of 20 m/s. Then the truck travels for 20 s at constant speed until the brakes are applied, stopping the truck in a uniform manner in an additional 5.0 s.

(a) How long is the truck in motion?

(b) What is the average velocity of the truck during the motion described?

2007-02-09 05:47:45 · 3 answers · asked by Erin C 1 in Mathematics

I read in the wikipedia that when refraction takes place wave length changes depending on the medium but the frequency remains the same. We know that the frequency and wavelength are inter-related. How can the frequency remain the same when the wavelength varaies?

2007-02-09 05:47:43 · 7 answers · asked by PLK 1 in Astronomy & Space

Question: the solar wind is a thin, hot gas given off by the sun. charged particles in this gas enter the magnetic field of the earth and can experience a magnetic force. suppose a charged particle traveling with a speed of 9.0e6 m/s encounters the earth's magnitude of 1.2e-7 T. assuming that the particle's velocity is perpendicular to the magnetic field at an altitude where the magnitude of 1.2e-7 T. assuming that the particle's velocity is perpendicular to magnetic field find the radius of...Find (a) an electron and (b) a proton

My Approach:

(a) electron
r = (9.11e-31)(9.0e6)/ (1.6e-19)(1.2e-7) = 427 m

(b) proton
r = (1.67e-27)(9.0e6)/ (1.6e-19)(1.2e-7) = 7.83e5 m

Book Answer: I don't have the answer to (a); however, for part (b) it is supposed to be 7.83e8 m. it's the reason why im posthing this question! appreciate the help

2007-02-09 05:47:03 · 2 answers · asked by Jimmy 3 in Physics

2007-02-09 05:46:49 · 25 answers · asked by Anonymous in Weather

Time, place, size,,extent, mortality, global effects please.

2007-02-09 05:45:14 · 8 answers · asked by madresicilia 2 in Earth Sciences & Geology

2007-02-09 05:42:50 · 9 answers · asked by cocada_us 1 in Astronomy & Space

A driver in a car traveling at a speed of 60 mi/h sees a deer 80 m away on the road. Calculate the minimum constant acceleration that is necessary for the car to stop without hitting the deer (assuming that the deer does not move in the meantime).

2007-02-09 05:37:17 · 5 answers · asked by Anonymous in Physics

My questions are: What happens to the energy that is created when the tectonic plates crash against or slip by each other? Wouldn't energy just keep building up with even greater force from each occurrence and wouldn't the energy be forced towards a specific direction? What would be the ultimate result from that ever-accumulating energy? Doesn't the visible evidence of the planet's land mass splitting apart (which could split Ethiopia and eventually perhaps other continents apart on dry land, too) an indication of that ever-accumulating and dangerously powerful energy building up, and again, to what end? Jean Rohlfing at jhr4games@yahoo.com.

2007-02-09 05:36:03 · 5 answers · asked by jhr4games 4 in Earth Sciences & Geology

2007-02-09 05:34:40 · 6 answers · asked by Anonymous in Weather

Does anyone know how to solve this? Thanks!

2007-02-09 05:33:18 · 2 answers · asked by Anonymous in Chemistry

Question: In a heart pacemaker, a pulse is delivered to the heart 81 times per minute. the capacistor that controls this pulsing rate discharges through a resistance of 1.8e6 ohms. one pulse is delivered every time the fully charged capacitor loses 63.2% of its original charge (CONFUSING!). what is the capacitance of the capacitor?

My Approach:
I went ahead and converted 81 pulses/minute to pulses/second (which is like 1.35 pulses/sec). I am having trouble plugging these numbers into an equation - q = q(initial)*e^(-t/RC). im not sure that's the equation to use. i would appreciate all the help i can get on this problem! even a fully solved problem would be cool.

Book Answer: 4.1e-7 F

2007-02-09 05:33:04 · 3 answers · asked by Jimmy 3 in Physics

Question: In a heart pacemaker, a pulse is delivered to the heart 81 times per minute. the capacistor that controls this pulsing rate discharges through a resistance of 1.8e6 ohms. one pulse is delivered every time the fully charged capacitor loses 63.2% of its original charge (CONFUSING!). what is the capacitance of the capacitor?

My Approach:
I went ahead and converted 81 pulses/minute to pulses/second (which is like 1.35 pulses/sec). I am having trouble plugging these numbers into an equation - q = q(initial)*e^(-t/RC). im not sure that's the equation to use. i would appreciate all the help i can get on this problem! even a fully solved problem would be cool.

2007-02-09 05:31:31 · 1 answers · asked by Jimmy 3 in Physics

Last fall, a gardener planted 65 iris bulbs. She found that only 56 of the bulbs bloomed in the spring.

How many of the bulbs should she plant next fall if she would like at least 92 to bloom

2007-02-09 05:30:02 · 4 answers · asked by Anonymous in Mathematics

In how many ways can 4 people sit in a row of 5 chairs?
I dont want the answer i want to know HOW TO DO it.
If anyone knows a site where they tell you how to do order problems, PLEASE post it. I'm horrible at these types of problems.

2007-02-09 05:29:57 · 4 answers · asked by gopistons 4 in Mathematics

by y= 40t - 16t^2. Find the velocity when t=2?

Don't I just have to plug in 2 for t. I did that but got wrong answer.

2007-02-09 05:29:05 · 6 answers · asked by Anonymous in Mathematics

the Chi Square and its probablility??

2007-02-09 05:26:58 · 1 answers · asked by jj 5 in Biology

A log with distinct tree rings is found buried in a sequence of Ice Age varves. What would you learn about the log by counting the tree rings? What would you learn about the log by counting the varves? What assumption is made when either method is used to determine absolute time?

2007-02-09 05:23:20 · 2 answers · asked by cassandra 1 in Earth Sciences & Geology

I'm reaserching the realtionship between a lonewolfs territory size, compared to a pack of wolfs territorry size. Our hypothesis is that a pack of wolfs is going to have a larger territorry size than a lonewolfs territory. Mainly I am looking for good sources either related articles or a valid internet baesed site.

2007-02-09 05:21:11 · 3 answers · asked by BlizzardRun07 2 in Zoology

can you explain the possible part played by an asteroid in the theory for the mass extinctions at the end of the Mesozoic.

2007-02-09 05:20:36 · 4 answers · asked by cassandra 1 in Astronomy & Space

A speedboat increases its speed uniformly from 20 m/s to 25 m/s in a distance of 200 m.

(a) Find the magnitude of its acceleration.

(b) Find the time it takes the boat to travel the 200 m distance.

2007-02-09 05:20:22 · 2 answers · asked by Anonymous in Mathematics

solve the equation

2007-02-09 05:20:00 · 4 answers · asked by sillyrainbow@sbcglobal.net 1 in Mathematics