Physics - November 2007

i was reading about tidal forces and gravity, and although they are interlinked with one another, i don t really understand their differences....can someone help me with that? explain to me the differences between tidal forces and gravity? thanks

2007-11-11 07:29:25 · 2 answers · asked by Anonymous

Finally, suppose m1 -> infinity, while m2 remains finite. What value does the the magnitude of the tension approach?

I think the answer is infinity but i'm not sure.

2007-11-11 06:38:35 · 1 answers · asked by Aeds 2

Hey,

I missed a class on Vertical Circular Motion.

If someone could please give me a brief lesson on it. How to figure out minimum speeds in regards to staying in the circle? How forces work at the top of circles(hill crest)/bottom of circles(hill valleys)/loops(within the circle)?? When Fc = Fg...? Regards to T=Fc+Fg?

Even a link to a site explaining this would be great. Thanks,

2007-11-11 06:35:00 · 2 answers · asked by ApolloLorne 3

What is the difference between them when used in a Resistance Temperature Detector (RTD) circuit. Wheatstone Bridge has a rheostat to balance the resistance, does the Callender-Griffith Bridge have a rheostat as well. Also why are three connecting wires used in the Callender-Griffith Bridge circuit. I've tried to find this elsewhere but they have just confused me more. All help is appreciated. I've asked the same in the Engineering Section too but that section is less popular so I thought I would try here. Thanks.

2007-11-11 06:32:53 · 3 answers · asked by Anonymous

In my physics class we have to design shoes so that we can walk on eggs the material can only be 10 cm thick and it has to resemble a shoe w/o any prefabricated shoes you must make them yourself. and be able to walk on eggs w/o crushing them. Any ideas?

2007-11-11 06:28:53 · 3 answers · asked by Anonymous

2007-11-11 06:24:49 · 1 answers · asked by Anonymous

2007-11-11 06:18:37 · 15 answers · asked by B W 1

Andy (mass 80 kg) uses a 3.0-m-long rope to pull Bob (mass 60 kg) across the floor ( mue=0.20 ) at a constant speed of 1.0m/s. Bob signals to Andy to stop by "plucking" the rope, sending a wave pulse forward along the rope. The pulse reaches Andy 150 ms later. What is the mass of the rope?

2007-11-11 06:16:44 · 2 answers · asked by rochesmk 2

two small spheres each with a mass of 0.20g are suspended by light strings from a common point. They are given the same electrical charge and come to equilibrium with each string at an angle of 5 degrees with the vertical. If the string is 30 cm long what is the magnitude of the charge on each sphere?

2007-11-11 06:09:22 · 1 answers · asked by centeroline76 1

A 4.52 kg block is pushed along the ceiling with a constant applied force of 85.9 N that acts at an angle of 60.5 degrees with the horizontal. the block accelerates to the right at 5.85 m/s^2. Find the coefficient of kinetic friction between the block anf the ceiling.

2007-11-11 05:59:50 · 1 answers · asked by Anonymous

Please explain to me how these problems are solved,I have noooo clue!

1) a baseball player slides into third base with an initial speed of 7.90 m/s. if the coefficient of kinetic friction between the player and the fround is .41, how far does the player slide before coming to rest?

2)a child does down a playground slide with an acceleration of 1.05 m/s2. find the coefficient of kinetic friction between the child and the slide if the slide is inclined at an angle of 35degrees below the horizontal.

3)hopping into your Porsche, you floor it and accelerate at 12m/s without spinning the tires. determine the minimum coefficient of static friction between the tires and the road needed to make this possible.

4)when you push a 180-kg book resting on a tabletop,it takes 2.25 N to start the book sliding.once it is sliding, however,it takes only 1.50N to keep the book moving with constant speed. what are the coefficients of static and kinetic friction between the book and the tabletop?

2007-11-11 05:57:43 · 1 answers · asked by Anonymous

How would you calculate this without knowing the mass of the second object?

2007-11-11 05:37:35 · 3 answers · asked by Anonymous

F(l)_____________F(r)
---->|2kg| |8kg| |6kg|<---
F(l) is the force on the left and is 12 N
F(r) is the force on the right and is 8N

2007-11-11 05:02:23 · 1 answers · asked by scoot 2

Here is the question:
Two balls of mud collide head-on in a perfectly inelastic collision. Their respective masses are m1=0.5kh and m2=0.25kg. m1 ismoving left to right before the collision with a speed of 4m/s and m2 is moving from right to left before the collision with a aspeed pf 3m/s. (a) Find the speed of the composite ball after the collsion (b) How much kinetic energy is lost during the collision?

2007-11-11 05:02:08 · 2 answers · asked by Anonymous

If it is possible, give at least one example.

2007-11-11 04:57:19 · 1 answers · asked by charm 1

An object, with mass m and speed v relative to an observer, explodes into two pieces, one two times as massive as the other; the explosion takes place in deep space. The less massive piece stops relative to the observer. How much kinetic is added to the system during the explosion, as measured in the observer's reference frame?

2007-11-11 04:51:58 · 2 answers · asked by Anonymous

Okay here's a question on my homework sheet and i don't even know where to start on it:

A daring cowboy/girl sitting on a tree limb whishes to drop vertically onto a horse galloping under the tree. The speed of the horse is 10m/s and the distance from the limb to the saddle is 3.0m. What must be the horizontal distance between the saddle and the limb when the cowboy/girl makes his/her move?

As I said i don't even know where to start

2007-11-11 04:50:45 · 5 answers · asked by stefany 1

I was under the impression that will be 0 at it highest point due to speed equals 0

2007-11-11 04:47:35 · 1 answers · asked by Vene 1

Recently our physics class tried an experiment in class where we measured impulse by having a cart slide off a basically frictionless ramp that's inclined. The cart hits a spring which is attached to a force sensor. We let the cart collide, and then stop the cart and watch the force sensor record the force vs. time graph.
We get the usual impulse peak, but immediately after that there are some really small bumps on the graph, and after that the graph levels out and has a slope of 0 again.
What do these bumps indicate, because this is happening after the cart has already gotten off the spring? How does this affect the momentum of the system?

2007-11-11 04:38:09 · 3 answers · asked by J Z 4

These are some that have stumped me. Feel free to try any yo ucan. How do you find the position formula if you just have the velocity? Thanks

A projectilve is fired straight upward with a velocity of 400 ft/sec.
What is the position formula?
Find the time and the velocity when it hits the ground
Find the maximum altitude achieved by the projectile
Find the acceleration at any time

A point is moving on a coordinate line has position function s(t)=t/\3-9t+1 on [-3,3]
Find the velocity at time t
Find the acceleration at any time
When is it moving to the left?
when is it moving to the right?
When is it stopped?

A projectile is fired directly upward with position s(t)=100-192t-16t/\2
Find the velocity?
Find the acceleration?
Find the maximum height?
Find the duration of the flight?
When is the velocity zero?
What is the intial veloctiy?
What was the speed at impact?

2007-11-11 04:16:37 · 4 answers · asked by crazicarly989 1

2007-11-11 03:58:07 · 4 answers · asked by norml 4

What amount of ice must be added to 540g of water at 25°C to cool the water to 0°C and have no ice remaining?

Enthalpy of melting: 6.02kJ/mol

2007-11-11 03:53:33 · 1 answers · asked by Anonymous

The coefficents of friction between the masses incline are mew sub s (u s)= 0.4 and mew sub k (u k)= 0.2
a. find the minimum force necessary to prevent the masses from sliding down the incline
b. find the tension in the rope reuslting from this force
*The masses are then given a brief push up the incline. Using the force found in part a), find

c. the acceleration of the system
d. the tension in the rope

*The masses are stopped and then given a brief push down the incline. Using the force found in part a) which continues to point up the incline, find
e. the acceleration of the system
f. the tension in the rope.

I know the answers, I just cannot figure out the work:
ANSWERS
a. 28 N
b. 14 N
c. 4.8 m/s2 down the incline
d. 14 N
e. 1.6 m/s 2 down the incluine
f. 14 N

2007-11-11 01:57:37 · 2 answers · asked by joe s 1

2007-11-11 01:31:42 · 4 answers · asked by Toilet Finger! 2

2007-11-11 00:51:37 · 15 answers · asked by Anonymous

17 letters, 2 words

2007-11-11 00:20:17 · 1 answers · asked by Anonymous

how can you prove it ? can you give a website for it?

2007-11-10 23:55:28 · 2 answers · asked by RANDOLPH PETER M 1

If I burn a piece of paper the flames are visible
The flames give off light (Form of EM).
My question is whether or not a flame also gives off other ElectroMagnetic radiation and if so in what part of the EM spectrum ???

2007-11-10 23:16:32 · 1 answers · asked by Eric K 1

2007-11-10 22:20:18 · 10 answers · asked by doodle_bug 2

Say a person could stand outside our Universe and is able to measure the progression of its expansion. And he has a twin on the other side.

At some point in time he will take another measurement and observe that the Universe has grown larger. But will an object within the Universe - in the form of his twin - be proportionately larger along with the Universe, or will he be the same size as the person outside the Universe?

I ask this because I was wondering why it is that "space" is expanding and not the objects within it.

If you have any questions before you want to answer, please post them. I will be checking in on this question over the next few days.

2007-11-10 18:16:36 · 4 answers · asked by Awesome Bill 7