Physics - September 2007

uhhhh what? i'm have no clue how to find these equations...can someone show me step by step so that i will know how to do them later...thanks in advance!!

1. Calculate the acceleration and the tension in the rope. For your variables use "m1", "m2", "theta1", "theta2" and "g". Assume all surfaces are frictionless, and the pulley and rope are massless and frictionless.

Diagram: http://www.webassign.net/userimages/48539?db=v4net

2. Find the acceleration for each of the following machines (use the same notation conventions as the previous problems; i.e. m1, m2, theta1, theta2, g, etc.).

Diagram 1: http://www.webassign.net/userimages/48540?db=v4net

Diagram 2: http://www.webassign.net/userimages/48541?db=v4net

Diagram 3: http://www.webassign.net/userimages/48542?db=v4net

2007-09-28 11:57:51 · 2 answers · asked by crazygirl0630 2

ahhh i hate physics!..i have never had to come up with equations myself before!!, if someone could show me how to work these problems so i can use it for future ones i would greatly appreciate it

1. Find equations for the acceleration and the tensions in the ropes. For your variables use "m1", "m2", "m3" and "g". Assume all surfaces are frictionless, and the pulley and rope are massless and frictionless. Let the left rope have tension T1 and the right rope have tension T2.

Diagram: http://www.webassign.net/userimages/48537?db=v4net

**I kinda started this one and got a=((m3-m2)*g)/(m1+m2+m3) but webassign said it was wrong!!

2. Calculate the acceleration and the tension in the rope. For your variables use "m1", "m2", "theta" and "g". Assume all surfaces are frictionless, and the pulley and rope are massless and frictionless.

Diagram: http://www.webassign.net/userimages/48538?db=v4net

2007-09-28 11:52:51 · 1 answers · asked by crazygirl0630 2

m1 is 1 kg and m2 is 3.5 kg. They are suspended from a frictionless pulley 14.9 m above the ground. The two masses are held even at 1.75 m above the ground. When the masses are released, what is the maximum height that the lighter mass will reach? Help on this would be great. I figured out the acceleration by adding the sum of the forces on m1 to the sum of the forces on m2. Now what do I do to figure out the distance traveled by m1? Do I figure out the time it takes m2 to hit the ground and then do something with that time?

2007-09-28 11:43:49 · 2 answers · asked by Jenn 1

A cable is lifting a construction worker and a crate, as the drawing shows. The weights of the worker and crate are 924 and 1510 N, respectively. The acceleration of the cable is 0.620 m/s2, upward.


(a) What is the tension in the cable below the worker?

? N

(b) What is the tension in the cable above the worker?

? N

2007-09-28 11:29:27 · 1 answers · asked by Anonymous

3. A rock is thrown straight up from the earth's surface. Which one of the following statements concerning the net force acting on the rock at the top of its path is true?

(a) It is equal to the weight of the rock.

(b) Because the rock is stationary, it is
instantaneously equal to zero.

(c) Since the direction of travel of the rock changes, its direction changes from up to down.

(d) Since the rock falls, it is greater than the weight of the rock.

(e) It is less than the weight of the rock, but greater than zero.

2007-09-28 11:00:46 · 3 answers · asked by surfing86 2

The escalator moves the man at a constant velocity from the ground level to the floor above, a vertical height of 4.80 m. What is the work done on the man by each of the following forces?
(a) the gravitational force

(b) the escalator







the last person who answered was wrong, please try and show work and answer. It woul dbe a big help

2007-09-28 10:51:33 · 1 answers · asked by Anonymous

Tell me

2007-09-28 10:13:44 · 8 answers · asked by Jack K 2

hello i am working on homework for physics since and i came across a question that i cannot solve! if you guys/girls could show me how to solve the following question i will greatly appreciate it

here it is:

a passenger in a hot-air balloon throws a ball with an unknown Vi. The ball accelerates at 9.8 m/s^2 [down] for 2 seconds, at which time its instantaneous velocity is 24 m/s[45 degrees below the horizontal]. Determine the ball's Vi.

the answer in the back of the book is: 17 m/s[10 degrees above the horizontal]

thanks a lot for any help

2007-09-28 09:48:22 · 1 answers · asked by Anonymous

Two capacitors are connected to each other in series as shown in the figure. The values of the capacitances are the following: C1 = 2.02 nF, C2 = 4.38 nF. What is their equivalent capacitance?

2007-09-28 09:46:57 · 1 answers · asked by Anonymous

A rocket is launched at an angle of 50.0° above the horizontal with an initial speed of 103 m/s. The rocket moves for 3.00 s along its initial line of motion with an acceleration of 28.0 m/s2. At this time, its engines fail and the rocket proceeds to move as a projectile.

(a) Find the maximum altitude reached by the rocket.


(b) Find its total time of flight.


(c) Find its horizontal range.

2007-09-28 09:35:40 · 1 answers · asked by Pulkit S 1

2007-09-28 09:33:25 · 1 answers · asked by Anonymous

2007-09-28 09:27:26 · 4 answers · asked by Anonymous

If one of the charges is halved in size, then the magnitude of the force halves.
If both of the charges are doubled in size, then the magnitude of the force remains the same.
If the distance between the charges is halved, then the magnitude of the force increases by a factor of four.

2007-09-28 09:18:59 · 3 answers · asked by Anonymous

Albert Einstein, Richard Feynman, Felix Bloch, Niels Bohr, Max Born, Muarry Gell-Mann, Lev Landau, Heinrich Hertz, Julian Schwinger, Albert A. Michelson, John von Neumann, Wolfgang Pauli, Steven Weinberg, Eugene Wigner, Edward Witten, Sheldon Glasgow, Edward Teller, J. Robert Oppenheimer, Leonard Susskind, Lee Smolin, Karl Schwarzschild, Tullio Levi-Civita are all Jewish.

2007-09-28 08:57:43 · 10 answers · asked by Anonymous

Last night my boyfriend were in the bedroom, the bedroom over head light was off, the switch also have a dimmer on the side of the switch to adjust how bright the light is. The switch was on, [OFF] position which is the switch down. Maybe an hour later, Thunder hit and then the bedroom lights came on really bright like when the dimmer is all the way up [when the switch was off], then dimmed back down the to lowest setting. I got freaked out and got up and checked the switch which was ...on, [ON] position when neither of us even touched it.

SO, can someone explain to me how a switch can turn it self upright when it was in down position OFF! without someone touching it???!

2007-09-28 08:40:22 · 4 answers · asked by Gabri3ll3 1

Suppose a Chinook salmon needs to jump a waterfall that is 1.50 m high. If the fish starts from a distance 1.02 m from the base of the ledge over which the waterfall flows, find the x- and y-components of the initial velocity the salmon would need to just reach the ledge at the top of its trajectory.
v0x =______ m/s
v0y =______ m/s

2007-09-28 08:23:08 · 1 answers · asked by P. Hysics 1

2007-09-28 08:11:40 · 4 answers · asked by Alexander 6

Time dimension properties
Trying to imagine that there’s a dimension which is elastic & moving with a certain unknown velcoity so u can feel its changes according to your high velocity imagine that balloon which is moving velocity taking it’s shape of your moving with as your moving through it & it can be rewind again to take all the shapes u made as an evidence for what u did, this is my opinion for time as a body,(EX: try to get any elastic thing & try to move your finger through it then start to return it back again u will notice that the elastic body will take all the shapes u did )
But the question is why if you are standing beside a rock for 100 year you will die while rock won’t effect (neglecting external effect like pressure & temperature)?(1st question)
May be because we r such complicated machine with some chemical reaction which destroy it self by it self
I think that time is only an evidence for what we did & its end is rewinding again like an elastic uncut able balloon to regain again to its beginning point, like an elastic point u start to stretch it from all direction till it became unable to be bigger so it start to regain its original shape a point & all things happened can be regain again, that’s my opinion about time as a body dimension but what if it’s an energy?(2nd question) , I think if time dimension is an unknown energy when its energy lost it starts to regain its shape again but may be faster or slower or same speed ,but its speed is too high as u need huge speed to feel the time changes in your frame relative to other ,but does time dimension has a relation with mass ??(3rd question) ,i mean what is created before other time or mass & does mass affects time dimension ??

2007-09-28 08:06:26 · 3 answers · asked by sherif m 1

This isnt entirely a physics question, but i couldnt think of a better place to put it.
One of the natural consequences of believing in God or the Creator of the universe is that the world is determined to at least some extent. How then do random events fit into this framework? are they still random and "out of Gods control"? or do they just look random to us? Examples of random events: atomic decay of a single atom, localization of particles from a waveform, and single shot measurements on probablility distributions of all sorts.


will choose best answer

2007-09-28 07:55:02 · 4 answers · asked by nacsez 6

Please, look at this question:
http://answers.yahoo.com/question/index?qid=20070928100815AA2qN2R

Now:
A sealed horizontal pipe on wheels, contants low-viscosity liquid and a a small bublle in the middle. Both liquid and the bubble are initially at rest with respect to the pipe.
http://i21.tinypic.com/352g4fd.jpg

The pipe rolls on wheels on level floor, and bounces off the wall. The spring attached to the end provides elastic bouncing.

What will happen to the bubble?

2007-09-28 07:32:04 · 3 answers · asked by Alexander 6

2007-09-28 07:22:44 · 3 answers · asked by pradeep p 1

2007-09-28 07:13:12 · 6 answers · asked by Alexander 6

hello i am learning how to solve problems in physics using components and i know how to use components generally but this question just makes it a little bit more complicated: here is it and i will really appreciate the help of how to solve it thanks alot

A watercraft with Vi = 6.4 m/s[E] undergoes an average acceleration of 2.0 m/2^2 [s] for 2.5 s. what if Vf of the watercraft?

the answer in the back of the book is 8.1 m/s [E 38 S]

again thanks alot

2007-09-28 07:09:46 · 2 answers · asked by Anonymous

C'est ok pour l'infiniment grand mais j'ai du mal à saisir l'infiniment petit .

2007-09-28 07:09:46 · 3 answers · asked by Anonymous

(Related to microwave devices ,this limitations leads to development of microwave devices)

2007-09-28 06:44:33 · 2 answers · asked by shibu 1

Plz could you answer! i am getting confused about it thanks

2007-09-28 06:36:35 · 8 answers · asked by athar 2

2007-09-28 06:25:47 · 7 answers · asked by Anonymous

A cannonball is fired from a cliff 140 m high downward at an angle of 27 degrees with respect to the horizontal. If the cannon's muzzle velocity is 34 m/s, what is the cannon ball's speed when it hits the ground?

I am not sure how to do this problem...I would appreciate any help on how to do it or example problems. (my book dosn't have any it just tells you the theory...)

2007-09-28 06:14:03 · 2 answers · asked by Anonymous

The bowstring exerts an average force of 80 N on the arrow over a distance of 0.75 m. With what speed does the arrow leave the bow?

2007-09-28 06:09:48 · 2 answers · asked by Anonymous

2007-09-28 06:08:15 · 3 answers · asked by Anonymous