Physics - December 2007

an airplane travels 1200 km at a speed of 1000 km/h. it then encounters a headwind that slows it to a 950 km/h for the next 1800 km. what is tge average speed in m/x for this trip?

thats an example... how do you convert.. what are all the conversions... like how many miles are in km ect all common ones please

2007-12-15 07:51:08 · 4 answers · asked by megan 1

thanks !

2007-12-15 07:47:02 · 3 answers · asked by Electra 2

ok, I can pretty much use any type of material. However, i cannot use parachutes or balloons, anything liek that. the shape in the end must be a common 3d shape like a sphere, cube, rectangle, cone, pyramid.....
ok, we can use anything but cannot glue anything to the egg. we can layer it with anything. Our grade depends on the size of the container. The size of a can of soda is an A, the bigger the lower the grade. anybody know?

2007-12-15 07:46:24 · 5 answers · asked by lisa rowe 2

A ball on the end of a string is cleverly revolved at a uniform rate in a vertical circle of radius 60.0 cm. Its speed is 4.30 m/s and its mass is 0.300 kg.

(a) Calculate the tension in the string when the ball is at the top of its path.
N
(b) Calculate the tension in the string when the ball is at the bottom of its path.
N

2007-12-15 07:23:36 · 1 answers · asked by Daydreamer 3

A 0.40 kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 1.2 m on a frictionless horizontal surface. The cord will break when the tension in it exceeds 61 N.

(a) What is the maximum speed the ball can have?

(b) How would your answer be affected if there were friction?

2007-12-15 07:21:07 · 1 answers · asked by Daydreamer 3

A fireman standing on a 12 m high ladder
operates a water hose with a round nozzle of
diameter 1.51 inch. The lower end of the hose
(12 m below the nozzle) is connected to the
pump outlet of diameter 2.98 inch. The gauge
pressure of the water at the pump is

P(guage of pump)= P(abs of pump)-P(atm)=81PSI=558.475 kPa

Calculate the speed of the water jet emerg-
ing from the nozzle. Assume that water is
incompressible liquid of density 1000 kg/m^3
and negligible viscosity. The acceleration of
gravity is 9.8 m/s^2. Answer in units of m/s.

2007-12-15 07:17:41 · 1 answers · asked by akanthasy 1

When a photon descontructively interfers with itself where does the energy go?

2007-12-15 05:51:46 · 4 answers · asked by Phillip 3

A 70.7kg high jumper leavs the ground with a vertical velocity of 6.2 m/s. The acceleration of gravity is 9.8m/s^2.

How high can she jump? Answer in units of m.

THANKS!

2007-12-15 05:43:03 · 3 answers · asked by Jordan K ® 3

reaction forces involving the rope. If the rope moves toward the white dog, what do you know about the forces on the rope?

2007-12-15 05:41:44 · 4 answers · asked by Anonymous

1. A light plank rests on two scales that read Fg1 = 450 N and Fg2 = 280 N. The scales are separated by a distance of 2.00 m. How far from the woman's feet is her center of gravity?


2.Two window washers, Bob and Joe, are on a 3.00 m long, 380 N scaffold supported by two cables attached to its ends. Bob weighs 765 N and stands 1.00 m from the left end. Two meters from the left end is the 500 N washing equipment. Joe is 0.500 m from the right end and weighs 850 N. Given that the scaffold is in rotational and translational equilibrium, what are the forces on each cable?

If I am missing information let me know. Thanks.

2007-12-15 05:34:12 · 1 answers · asked by loveall 3

Can you give me an explanation with the original equations for these problems? I have a bunch more, but if these are explained to me, I'm sure I can get the rest.

1. A 3.91 kg briefcase is sitting at rest on a level floor. The acceleration of gravity is 9.81 m/s^2.
What is its acceleration (answer in units of m/s^2)?
What is its weight (Answer in units of N.)?
2. Once a 26 kg crate is in motion on a horizontal floor, a horizontal force of 52N keeps the crate moving with a constant veloctity.
The acceleration of gravity is 9.81 m/s^2.
What is the coefficient of knetic friction, between the crate and the floor?

Ok, so I realize this is my homework and i need to do it myself, so I am going to stop putting problems up, but I was looking at the rest and It would be great if someone could tell me how to find the coefficient of static friction, coefficient of kinetic friction, and how to find those if they give me degree measures to use also.

2007-12-15 05:10:08 · 2 answers · asked by 5.8caloriewater 2

A 42 kg of ice slides down the plane incline 34 degrees in the figure. Assuming friction is negligible, what is the acceleration of the block down the incline? If the kinetic coefficient of friction is 0.060, what is the acceleration of the block down the incline?

Please show and explain all work. Please show the formula or formulas that were used.

2007-12-15 04:52:09 · 2 answers · asked by Anonymous

I think that they are just small pariccles of water (not steam)

2007-12-15 04:41:50 · 13 answers · asked by Cars are #1 2

Describe the ball's acceleration?

2007-12-15 04:34:59 · 10 answers · asked by Anonymous

wind, solar, fossil fuel or geothermal???

2007-12-15 04:04:45 · 26 answers · asked by Anonymous

It seems to me that if time travel to the past were possible that every configuration of matter in the universe at each of the tiniest possible intervals of time would have to be stored somehow, or the state of the entire universe at each instant in history would all have to exist simultaneously. Can you think of any way in which you could get to the past without needing a record of each moment of the past to somehow still exist? I don't know how to put this any more clearly. I hope someone understands what I mean.

2007-12-15 04:00:41 · 10 answers · asked by Meatball 2

2007-12-15 03:56:49 · 2 answers · asked by Jenny D 1

which energy: wind energy, solar power, fossil fuels, geothermal energy????

2007-12-15 03:54:47 · 10 answers · asked by Anonymous

2007-12-15 03:50:14 · 4 answers · asked by Anonymous

why do fossil fuels eg. coal have energy ie the energy source of the fossil fuel.

2007-12-15 03:49:07 · 7 answers · asked by Anonymous

A 42 kg of ice slides down the plane incline 34 degrees in the figure. Assuming friction is negligible, what is the acceleration of the block down the incline? If the kinetic coefficient of friction is 0.060, what is the acceleration of the block down the incline?

Please show and explain all work. Please show the formula or formulas that were used.

2007-12-15 03:40:47 · 3 answers · asked by Kantilal P 1

A horizontal force of 5 N accelerates a 4 kg mass, from rest, at a rate of 0.5 m/s^2 in the positive direction. What frictional force acts on the mass? What friction acts on the mass? What is the coefficient of friction for the surfaces in contact?

Please show and explain all work. Please show the formula or formulas that were used.

2007-12-15 03:37:41 · 2 answers · asked by Kantilal P 1

It is related to the spectrum of light.

2007-12-15 02:43:07 · 4 answers · asked by isabella 1

2007-12-15 02:41:29 · 3 answers · asked by Joshua 2

2007-12-15 02:39:26 · 3 answers · asked by Joshua 2

Seems to have the same smell as the Cosmological Constant.

2007-12-15 02:30:22 · 2 answers · asked by bradxschuman 6

2007-12-15 02:26:39 · 1 answers · asked by jmarcus10 1

2007-12-15 02:20:18 · 4 answers · asked by Anonymous

the options are 1.10^15 2. 10^17 3.10^21 4. 10^27 5. 10^33 .also plz explain the answer to me

2007-12-15 01:56:33 · 1 answers · asked by usama s 1

Silver and white surface both reflect all wavelengh of visible light. But why silver look silver and white look white?

2007-12-15 01:28:50 · 4 answers · asked by Anonymous