Physics - November 2007

An 0.8-kg object is attached to one end of a spring and the system is set into simple harmonic motion. Please take the values of A and T as: A = 0.091 m and T = 1 s. If the amplitude, A, of the motion is .091m, and angular frequency omega is 6.283 rad/s and the spring constant is 31.582, then
a) Find the speed of the object at t=3s
b) Find the magnitude of the objects acceleration at t=3s

2007-11-08 15:56:03 · 1 answers · asked by Bob P 1

Could someone please tell me how to find acceleration when you are only given mass? Below is the force problem I am trying to solve:
A 20 kg wooden crate falls from a truck when it is traveling along a straight and level road at 25 m/s. If the crate slides for a distance of 80m in coming to rest, find acceleration.

I would appreciate it if someone would help.

2007-11-08 15:39:29 · 4 answers · asked by mangomantra 1

The cube is heated to 135°C from 25°C. What is the increase in the surface area of the cube? (Hint: The length of each edge of the cube expands when heated.)

2007-11-08 15:17:26 · 1 answers · asked by Anonymous

what is the difference between a speed graph and an acceleration graph? i am supposed to think abou the formulas u use when calculating each.

2007-11-08 15:16:36 · 1 answers · asked by Sarah S 3

The specimen is heated to 95.0°C and then placed in a 0.13 kg copper vessel that contains 0.089 kg of water at equilibrium at 25.0°C. The loss of heat to the external environment is negligible. When equilibrium is established, the temperature is 27.0°C. What is the specific heat capacity of the specimen?

2007-11-08 15:16:06 · 1 answers · asked by Anonymous

A 190 N sphere 0.20 m in radius rolls, without slipping 6.0 m down a ramp that is inclined at 28° with the horizontal. What is the angular speed of the sphere at the bottom of the hill if it starts from rest?

2007-11-08 14:56:08 · 1 answers · asked by Butterfly <3 2

Here's the question from the text book for my home work:
An object that weighs 340 N is floating on a lake. What is the buoyant force on it? What is the weight of the displaced water?

Is this even possible to solve, if so, can you send me the equation or something?

2007-11-08 14:33:33 · 3 answers · asked by Anonymous

4. Two air track carts move toward one another on an air track. Cart 1 has a mass of .45kg and a speed of 1.1 m/s. Cart 2 has a mass of .65kg (a) what speed must cart 2 have if the total momentum of the system is to be zero.(b) since the momentum of the system is also zero, does it follow that the kinetic energy of the system is also zero? (c) verify your answer to pat (b) by calculating the system’s kinetic energy.
6. A 220- g ball falls vertically downward hitting the floor with a speed of 2.5 m/s and rebounding upward with a speed of 2 m/s. (a) find the magnitude of the change in the ball’s momentum (b) find the change in the magnitude of the ball’s momentum (c) which of the two quantities calculated in parts (a0 and (b) is more directly related to net force acting on the ball during the collision with the floor? explain?

2007-11-08 14:28:33 · 1 answers · asked by CA-C 1

Why does electromagnetic radiation in the ultraviolet region represent a larger energy transition than does radiation in the infrared region?

2007-11-08 14:26:39 · 1 answers · asked by Redfalcongt 2

trying to photograph a piece of petrified rock to show the mineral colors in the rock itself......any suggestions welcomed

2007-11-08 14:09:08 · 3 answers · asked by sandyjay@sbcglobal.net 1

A 145 kg block is released at a 4.6 m height
as shown. The track is frictionless. The block
travels down the track, hits a spring of force
constant k = 1109 N/m:
The acceleration of gravity is 9.8 m/s2 :
Determine the compression of the spring x
from its equilibrium position before coming to rest momentarily. Answer in units of m

2007-11-08 13:39:16 · 2 answers · asked by yoyoyoyoyoyo 2

2007-11-08 13:16:05 · 3 answers · asked by Robert R 2

It is said that Galileo discovered a basic principle of the pendulum-that the period is independent of the amplitude-by using his pulse to time the period of swinging lamps in the cathedral as they swayed in the breeze. Suppose that one oscillation of a swinging lamp takes 5.5 s. How long is the lamp chain? What maximum speed does the lamp have if its maximum angle from vertical is 3.0 degrees?

2007-11-08 13:03:57 · 1 answers · asked by rochesmk 2

A fisherman in a boat is using a "10-lb test " fishing line. This means that the line can exert a force of 45 N without breaking.. (1lb=4.45N).

(A) How heavy a fish can the fisherman land if he pulls the fishup vertically at constant speed?

B: If he accelerates the fish upwards at 2.0 m/s^2 what maximum weight fish can he land?


Now i have no clue what to do in this. I am so lost. Im pretty sure this has to do with Newtons laws or soemthing. Any help would be awesome!

2007-11-08 12:38:39 · 2 answers · asked by Anonymous

I really need this answer or I'm going to fail my science homework.

2007-11-08 12:27:47 · 4 answers · asked by piano man 1

(a) In what direction, relative to the shore, does Dave's boat go?
°
(b) How long does it take Dave to cross the river?
s
(c) How far downstream is Dave's landing point?
m


I am trying to use the pathag therom, but my anwers are still coming out wrong. The trig functions are also confusing so if someone could explain them to me that would be great

2007-11-08 12:21:19 · 2 answers · asked by Trying M 1

2007-11-08 12:07:53 · 1 answers · asked by navya 1

For me it is that physics is the ultimate of sciences. It reveils all and brings awe to me everywhere I look.

2007-11-08 12:07:42 · 2 answers · asked by Ticeto 1

2007-11-08 12:06:19 · 1 answers · asked by navya 1

why is this a graph of constant speed? http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade10/math/images/12graphicaa.gif
i don't know how to explain.

2007-11-08 12:04:53 · 2 answers · asked by Sarah S 3

2007-11-08 12:02:55 · 7 answers · asked by Anonymous

A child sits in a wagon with a pile of 0.47 kg rocks. If she can throw each rock with a speed of 9 m/s relative to the ground, causing the wagon to move, how many rocks must she throw per minute to maintain a constant average speed against a 3.5 N force of friction?







Thanks so much for your time!!!

2007-11-08 11:54:51 · 1 answers · asked by RussianSoccer3 1

Hi,

I am a "young" kid in 7th grade, so your answers should be simple. In a form like Speed = distance/time. Like an understandable and well explained form.

So how do I calculate initial speed if I have got:
acceleration : 8 m/s 2
time: 5 s
final velocity: 30 m/s

Thanks!

2007-11-08 11:51:02 · 2 answers · asked by Cloetta 2

why is this a graph of constant speed? http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade10/math/images/12graphicaa.gif
i don't know how to explain.

2007-11-08 11:49:38 · 4 answers · asked by Sarah S 3

Help me and show me please

2007-11-08 11:43:56 · 1 answers · asked by Shawn Carter 1

The "cornering performance" of an automobile is evaluated on a skid pad, where the maximum speed that a car can maintain around a circular path on a dry, flat surface is measured. Then the centripetal acceleration, also called the lateral acceleration, is calculated as a multiple of the free-fall acceleration g. The main factors affecting the performance of the car are its tire characteristics and the suspension system. A certain car can negotiate a skidpad of radius 62.2 m at 80.5 km/h. Calculate its maximum lateral acceleration.

2007-11-08 11:42:08 · 1 answers · asked by Anonymous

2007-11-08 11:31:48 · 8 answers · asked by Anonymous

this isnt the project or a question its kind of last minute so i really need sum answers =]

2007-11-08 11:06:06 · 5 answers · asked by Lauu re nnnn,! 1

http://www.members.shaw.ca/truth911/truth911/towers.htm

Molten Metal on 9/11 - impossible to create from an air fire! :
http://www.youtube.com/watch?v=JithuVAIb7Y

Controlled demolitions of 3 WTC buildings:
http://www.youtube.com/watch?v=Qa7PN-8T2VY

Building 7 was not hit by any plane or seriously damaged:
http://www.youtube.com/watch?v=EZ9BofDUXv0
http://video.google.com/videoplay?docid=2073592843640256739

Flight 93 - where is the wreckage and debris? :
http://www.youtube.com/watch?v=-59kouBgO_s&NR=1

Pentagon - where is the 80 tonnes of jet plane debris? :
http://www.youtube.com/watch?v=Rgyq2H7PpO0
http://www.youtube.com/watch?v=lSeaZLYViwU

"9/11 Mysteries" - detailed scientific analysis of what happened on 9/11:

Part 1:
http://video.google.com/googleplayer.swf?docId=-8452331984890658202&hl=en

Part 2:
http://video.google.com/googleplayer.swf?docId=1018616329475082196&hl=en

Part 3:
http://video.google.com/googleplayer.swf?docId=6024263701753064760&hl=en

http://truth911.net

2007-11-08 11:05:39 · 7 answers · asked by 911weknow .com 1

It takes 333.51J to melt excatly 1g of H2O. What is the molar heat of fusion for water, from this data?

5.99kJ/mol?
Did I get it?

2007-11-08 11:03:51 · 1 answers · asked by C'est Comme Un Rêve 3