Physics - November 2007

For any standing wave, how do you find the amplitude at a given point?

2007-11-09 10:06:59 · 2 answers · asked by Anonymous

The ultrasonic motion sensor sends pulses of ultrasound toward a cart on the low-friction track and determines the distance by the time an echo takes to return. The temperature in the lab is equal to 20 degrees C.

2007-11-09 10:05:05 · 1 answers · asked by triciawin87 2

I'm planning a trip to the "land down under", and my mom started making jokes about stuff falling out of my pocket (because I'll be on the bottom of the globe) and such. This led to a discussion about why people DON'T fall off the bottom of the earth. I Googled it and found several scientific explanations, but I would like someone to explain it to me in simple layman's terms.

Thanks in advance.

2007-11-09 09:57:19 · 13 answers · asked by Nicole 3

My friend showed me a homemade accelerometer which consisted of a cork floating at the top of a jar of water. The cork is attached to the bottom of the jar using a length of thread. During sudden movements, the cork moves toward the direction of acceleration which seems to defy Newton's 1st Law of inertia. How does this work?

2007-11-09 08:45:02 · 0 answers · asked by matpatstery 1

Don Guzzilani called his leutenant into the office and told him:

'That truck in parking lot has the body of Fat Toni in the trunk.
We finally got him yesterday, Johnny. Drive to Hudson river and dispose of the body. Concrete bricks are in the bed of the truck, 20lb each. Those are good bricks, too, made of high density concrete, twice as dense as water.

And keep in mind that the body will swell in the water and its volume will double. Do not fail me, Johnny, this time. And you may keep Fat Tony's wallet.'

Jonny walked to the car and checked the wallet. Inside he found 20 crispy $100 bills and driver's licence, which read:
Name: Antonio Fattini
DOB: 01/02/60
Weight: 300lb
Height: 5'8''
Expires 01/02/08

2007-11-09 07:55:13 · 5 answers · asked by Alexander 6

away was the explosion?

2007-11-09 07:09:55 · 2 answers · asked by MeDIGURU 1

i have asked this question and recieved many different answers:

An elevator has a mass of 900kg, at most it uses a force which is equivalent to 17kN. How many people who weigh 75kg can the elevator maximum take?

http://answers.yahoo.com/question/index;_ylt=AkTtEbFTcQsvI1mp2zXgu3Tsy6IX;_ylv=3?qid=20071109074401AAx8atq

which one is right and why?


thanks for your time.

2007-11-09 07:02:31 · 2 answers · asked by Essien 3

The puck in Figure P8.51 has a mass of 0.200 kg. Its original distance from the center of rotation is 40.0 cm, and it moves with a speed of 90.0 cm/s. The string is pulled downward 15.0 cm through the hole in the frictionless table. Determine the work done on the puck. (Hint: Consider the change of kinetic energy of the puck.)

2007-11-09 07:01:32 · 1 answers · asked by ricahrd l 1

Please give examples to! thanks!

2007-11-09 06:58:31 · 1 answers · asked by Anonymous

Suppose that an apple at the top of a tree is pulled by earths gravity with a force of 1 newton another apple rests at the top of another tree that is twice as tall as the first would the force of gravity on the apple in the second tree be 1/4 as strong as that of the first?

2007-11-09 06:49:58 · 3 answers · asked by blond_n_punk 2

You are assigned the design of a cylindrical, pressurized water tank for a future colony on Mars, where the acceleration due to gravity is 3.71 meters per second per second. The pressure at the surface of the water will be 125 kPa, and the depth of the water will be 13.5 m. The pressure of the air in the building outside the tank will be 95.0 kPa.

Find the net downward force on the tank's flat bottom, of area 2.25 m^2, exerted by the water and air inside the tank and the air outside the tank.
Express your answer numerically in Newtons, to three significant figures.

2007-11-09 06:39:28 · 2 answers · asked by jmr_487 2

A string with non-negligible mass m is attached to the ceiling and hangs vertically. You flick the string and create a transverse wave. As the pulse travels up the string, does the wave speed increase, decrease, or stay the same?

This problem was from my physics exam. I am uncertain of the logic of the correct answer. Any help would be appreciated. Thank you.

2007-11-09 06:38:06 · 4 answers · asked by kmaster2007 1

A particle, starting from point A in the drawing at a height h0 = 3.3 m, is projected down the curved runway. Upon leaving the runway at point B, the particle is traveling straight upward and reaches a height hf = 4.7 m above the floor before falling back down. Ignoring friction and air resistance, find the speed of the particle at point A.
________ m/s

http://www.webassign.net/CJ/06_82alt.gif

2007-11-09 06:16:19 · 1 answers · asked by Anonymous

http://en.wikipedia.org/wiki/Oblate
Is the short polar axis oriented vertically or horizontally?

2007-11-09 06:15:49 · 2 answers · asked by Alexander 6

2007-11-09 05:58:00 · 6 answers · asked by Alexander 6

2007-11-09 05:42:43 · 2 answers · asked by Anonymous

By how much intensity of the light that passes through will change if third polarizer is inserted between them at angles 30° to both polarizers.

2007-11-09 05:38:59 · 1 answers · asked by Alexander 6

A simple pendulum with a length 1.50 m makes 81.6 oscillations in 180 s. What is the acceleration due to gravity at its location? (It is not located on Earth!)

2007-11-09 05:29:12 · 3 answers · asked by Anonymous

-What is the buoyant force on the object?
-Will this object float or sink? Explain your answer.

2007-11-09 05:25:29 · 3 answers · asked by Anonymous

2007-11-09 05:16:59 · 18 answers · asked by mr perfect 4

If the merry go round starts at rest and aquires an angular speed of 0.0870rev/s in 3.50s what is its mass?

2007-11-09 05:10:39 · 1 answers · asked by luawaikuuipo 1

2007-11-09 05:09:53 · 7 answers · asked by Anonymous

the other end. Where should a 1.80kg container of orange juice be placed so that the basket balances at the center?

2007-11-09 05:07:50 · 1 answers · asked by luawaikuuipo 1

one end. a)where should a parent push vertically downward with a force of 210N in order to hold the teeter totter level? b) where should the parent push with a force of 310N? c) How would you answer to parts a and b if the mass of the teeter totter was doubled.

2007-11-09 05:01:47 · 1 answers · asked by luawaikuuipo 1

A wooden block with mass 1.85 kg is placed against a compressed spring at the bottom of a slope inclined at an angle of 34.0 degrees (point A). When the spring is released, it projects the block up the incline. At point B, a distance of 6.95 m up the incline from A, the block is moving up the incline at a speed of 7.30 m/s and is no longer in contact with the spring. The coefficient of kinetic friction between the block and incline is mu_k = 0.550. The mass of the spring is negligible.

2007-11-09 04:37:17 · 1 answers · asked by bg 1

Hoover Dam was built in the 1930s to provide electricity for the southwest U.S. and to prevent the wild Colorado River from flooding. Hoover Dam is about 380 m wide and is about 221 m high. Assume that Hoover Dam can be approximated by slab geometry with a width of 380 m (W). What is the total force (newtons) on the dam face if the water level from Lake Mead (holding basin for Hoover Dam) is 200 m (D)? Assume the density of water in Lake Mead is 1000 kg/m3.

2007-11-09 04:32:09 · 1 answers · asked by Justin O 2

Density of concrete is about 1.8-2.3 times that of water (and hence that of victim's body).
http://hypertextbook.com/facts/1999/KatrinaJones.shtml

2007-11-09 04:03:31 · 3 answers · asked by Alexander 6

2007-11-09 04:01:37 · 5 answers · asked by IshotJR 2

19) what is the critical angle for diamond (n= 2.42)?

20) A diver below the surface of a lake notices that no light appears to be coming toward her greater then the angle theta, measured from the vertical. If the index of refraction of water is 1.33, what is the angle of theta??


please help me and explain this to me, I'm having a hard time, thanks

2007-11-09 03:50:00 · 3 answers · asked by Anonymous

2007-11-09 03:30:10 · 8 answers · asked by wayne8574 1