Physics - December 2006

object #1 slides along a surface (μk = 0.15) that makes a 20º angle with respect to the horizontal. Both objects are connected by a massless string that runs over a frictionless pulley (m = 10 kg, r = 0.25 m). Object #1 has a mass of 5 kg and object #2 has a mass of 20 kg. Apply Newton’s Second Law to each of the three objects to obtain a system of three equations and three unknows that can be solved to find the tensions and acceleration of this system. Then calculate the final speed of object #2 after dropping a distance of 2 m.

2006-12-11 01:17:05 · 3 answers · asked by Anonymous

2006-12-11 00:41:25 · 25 answers · asked by Anonymous

where i and j are unit vectors directed east and north respectively.

a) Find the distance of the ship fromthe lighthouse when t = 60?

b) Find the times when the ship is
i) Due north of the lighthouse?
ii) North east of the lighthouse?

2006-12-11 00:39:16 · 4 answers · asked by Ritch 3

where a is a constant and i and j are unit vectors directed north and east respectively.

a) The boat is heading due north when t = 2. Find a?

b) Find:
i) the initial velocity of the boat?
ii) the acceleration of the boat?

c) Find the distance between the initial position of the boat and its position when t = 2??

2006-12-11 00:30:16 · 5 answers · asked by Ritch 3

Iam not clear enough to provide details.

2006-12-11 00:19:49 · 5 answers · asked by harshini m 1

From Archimedes' principle, we know that buoyancy of a liquid is inversely related to mass of the liquid displaced. But the formula for force is mass*acceleration which makes force directly related to mass. Since buoyancy is also a force, this is confusing. Can someone please give an explanation for this?

2006-12-10 22:44:37 · 5 answers · asked by Bezoar 2

In length

Ruler, meter stick or tape measurer?

In mass

Clinical weighing scale or Ordinary Weighing Scale?

In time

Wrist watch or Stop Watch?

2006-12-10 22:17:29 · 3 answers · asked by Samlovesjesea 1

:) thanks... =)

2006-12-10 22:04:51 · 3 answers · asked by Misa 1

...and drop an object through it, what happens in relation to gravity? Does the object get half way, then fall the other way - or reach a point where it endlessly goes back and forth?

2006-12-10 22:00:19 · 17 answers · asked by geefunken 2

why is a jeepney of mass 2000kg more difficult to stop than a tricycle of mass 1000 kg when both are traveling at the same initial speed. its a practical question, but answer it scientifically (physics) :)

2006-12-10 21:57:12 · 4 answers · asked by Misa 1

Listen to this very carefully!!This is about Radioactivity

A radioisotope decays by alpha emittion. Now these alpha particles contain 2 protons and 2 neutrons as we all know...(this is why we call them helium nuclei) BUT if the Nuclei that emits it was neutral before, and had lost two protons and 2 neutrons by emittion...What happened to the electrons in the atom? If beta is not emitted as well, it should remain in its place in the parent atom(that emits) and cause it to have a Negative Charge after the emittion!!! Am i Right??

2006-12-10 21:44:51 · 6 answers · asked by Fahd 2

begins to chase the dog with an acceleration of .5 m/s^2. H ow many seconds does it take the chef to catch the dog?

2006-12-10 20:57:55 · 4 answers · asked by Bob Nguyen 1

Are there solar systems which are composed of two stars, or 2 "suns" instead of one? What are the terms, scientific or common, used to describe such systems? And is it possible for such systems to have planets ? Could those planets be revolving around both suns, and does such case, if it is possible, have a scientific term to describe it?

2006-12-10 20:52:33 · 2 answers · asked by bunkushbunkush 3

I mean a Huge Nuclear Fussion reactor that will be enormous in size and it will be built with the WHOLE worlds co-operation.It will not only meet the needs of the country in which it is situated but also the WHOLE world.Your viewpoints in this direction?

2006-12-10 19:26:01 · 6 answers · asked by mb15_ind 2

when it reaches the top of the lake

2006-12-10 19:11:07 · 14 answers · asked by Anonymous

I am looking for any relationship that talks about relation between static charge i.e ESD in a room and the particle count. I am told that high particle count can lead to high static charge activity in the area. If yes, is there a method for determining the same. Please help

2006-12-10 19:03:09 · 4 answers · asked by nivanp 2

2006-12-10 19:01:37 · 5 answers · asked by Anonymous

2006-12-10 18:33:56 · 7 answers · asked by Anonymous

Sometimes, at night, I hear someone breathing as if they were in my room, but there's no one but me. I've thought it might come from the people upstairs or from my parents' room, which is beside mine, but the breathing is too clear to come from outside.
It's driving me crazy, though it never lasts too long.
Is there a logical, physical, non-superstitious reason for that? I.e., something in the architecture of our building.

2006-12-10 18:20:51 · 6 answers · asked by Anonymous

2006-12-10 18:09:24 · 11 answers · asked by Navaneet 1

the atom having more than 4 valence electron are conductor in nature, those having less than 4 or having non are Insulator and those are having exactly 4 valence electron are called semiconductor. The best known Semiconductor are Silicon(Si) and Germanium(Ge)
having 4 valence electron in their outermost orbit. Carbon is also having 4valence electron in outemost orbit but is not a semiconductor. Why?

2006-12-10 17:55:31 · 8 answers · asked by hansi 1 1

When a stone is dropped into water, the resulting ripples spread farther and farther out, getting smaller and smaller in amplitude until they disappear. Why does that happen?

2006-12-10 17:35:59 · 6 answers · asked by heyheyhey 2

At time zero a 0.27 kg book is sliding at 10.0 m/s, left. Bill is pushing the book with a force of 3.4 N, left, but the acceleration is 4.0 m/s^2, right. Calculate (a) the friction force (mag. & dir.) and (b) the velocity (mag. & dir.) after 1.5 s.

I've drawn a diagram but I don't understand how to solve. I'm not sure which equations to use or anything like that.

2006-12-10 17:20:26 · 3 answers · asked by acollins121 2

A car traveling at 30 m/s undergoes a constant negative acceleration of magnitude 2.00 m/s^2 when the brakes are applied. How many revolutions does each tire make before the car comes to a stop assuming the car does not skid and the tires have a radii(plural form of radius) of .300 meters?

2006-12-10 16:47:46 · 5 answers · asked by elguapo_marco_2008@sbcglobal.net 3

A worker pushes a 1.50x10^3 N crate with a horizontal force of 345 N a distance of 24.0m. Assume the coefficient of kinetic friction between the crate and the floor is 0.220.

b) How much work is done by the floor on the crate?

Uk=Fk/Fn Fk=0.220; Fk=? ; Fn= 1.50x10^3 N
Fk=330N

W=F(d)
W=(-15N)(24.0m)
W= -3.6x10^2 J

Right?

2006-12-10 16:46:52 · 4 answers · asked by billf39 2

Imagine a space station which rotates to create artificial gravity (like in "2001: A Space Odyssey" or "Babylon 5".)

Suppose there is an Olympic size swimming pool in the outer ring.

Would the surface of the water in the swimming pool be flat or curved?

2006-12-10 16:22:38 · 5 answers · asked by Wolf Harper 6

A 0.075kg ball in a kinetic sculpture is raised 1.33 m above the ground by a motorized vertical conveyor belt. A constant frictional force of 0.350N acts in the direction opposite the conveyor belt's motion. How much total work is done in raising the ball?

What i did:
0.075 kg * 9.81m/s^2 = 0.73575 N = weight force of ball on earth

down forces= 0.736 N + 0.350N = 1N
Opposite force is 1N since acc is constant

Wnet = Fnet (d) (cos ??)
Wnet = (1N) (1.33m)
wnet = 1.33 J

RIGHT??

2006-12-10 16:16:20 · 4 answers · asked by billf39 2

Electricity I know, but in more detail. I have forgotten what I learned in Physics. That rasies another question, I have only been out of college for one year, I feel like I have forgotten alot of material already, specifically math, physics, even english and spelling. Have others? I hope I didnt drink too much beer in school. Thanks.

2006-12-10 16:02:21 · 13 answers · asked by Ryan 1

2006-12-10 15:55:49 · 6 answers · asked by Sarya D 1

2006-12-10 15:40:38 · 11 answers · asked by Anonymous