Physics - November 2007

I have a line of length 66 ft. on each side of the line there is a triangle. the triangle on top has twice the area of the triangle on the bottom. Both triangles are right triangles with slopes = -1576. how long are each triangle??? Oh, and the height of the top triangle minus the height of the little triangle = 104000

http://img221.imageshack.us/img221/9838/aaare3.png

2007-11-20 04:58:20 · 1 answers · asked by Anansi 2

just think...

2007-11-20 04:57:51 · 3 answers · asked by Raj 2

The work function of an element is the energy required to remove an electron from the surface of the solid element. The work function for lithium is 279.7 kJ/mol (that is, it takes 279.7 kJ of energy to remove one mole of electrons from one mole of Li atoms on the surface of Li metal). What is the maximum wavelength of light that can remove an electron from an atom on the surface of lithium metal?

2007-11-20 04:56:15 · 1 answers · asked by jotham4200 1

http://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Wooden_hourglass.jpg/277px-Wooden_hourglass.jpg

Is weight diminished by amount of sand in fall at any given moment of time?

2007-11-20 04:27:54 · 8 answers · asked by Alexander 6

I'm pretty familiar with chemistry and physics, however, why do we assume that all of the elements must be on earth ? Isn't it possible that there exist some elements at the end of the table we haven't discovered yet ?

2007-11-20 03:34:07 · 8 answers · asked by Razor 2

If I were in a zero-gravity environment with a tennis ball.
The tennis ball would be attracted to my gravity, bringing it close to me?

2007-11-20 03:20:14 · 8 answers · asked by Jansen J 4

What is rest mass Mo of the PAIR of photons?

2007-11-20 03:19:50 · 4 answers · asked by Alexander 6

2007-11-20 03:13:24 · 4 answers · asked by Anonymous

When we are inside a room why is there the same air pressure as when we are outside. Surely the roof takes all the pressure from the gas etc above and therefore it is not on us.

2007-11-20 03:12:07 · 4 answers · asked by Anonymous

A cat chases a mouse across a 1.0 m high table. The mouse steps out of the way, and the cat slides off the table and strikes the floor 2.2 m from the edge of the table. When the cat slid off of the table, what was its speed?

2007-11-20 03:08:50 · 3 answers · asked by x x italian baby x x 1

A person doing a chin-up weighs 710 N, disregarding the weight of the arms. During the first 27.0 cm of the lift, each arm exerts an upward force of 365 N on the torso. If the upward movement starts from rest, what is the person's speed at this point?

2007-11-20 03:05:23 · 1 answers · asked by andyjumpman23 3

The active element of a certain laser is an ordinary glass rod 25 cm long and 1.0 cm in diameter. If the temperature of the rod increases by 73°C.
(a) Find its increase in length.

(b) Find its increase in diameter.

(c) Find its increase in volume.

2007-11-20 02:53:05 · 1 answers · asked by ricahrd l 1

A helium-filled balloon at atmospheric pressure is tied to a 2.7 m long, 0.100 kg string. The balloon is spherical with a radius of 0.40 m. When released, it lifts a length (h) of the string and then remains in equilibrium as in Figure P9.78. Determine the value of h. When deflated, the balloon has a mass of 0.25 kg. (Hint: Only that part of the string above the floor contributes to the load being held up by the balloon.)

2007-11-20 02:50:56 · 3 answers · asked by ricahrd l 1

Superman attempts to drink water through a very long straw. With his great strength he achieves maximum possible suction. The walls of the tubular straw don't collapse.
(a) Find the maximum height through which he can lift the water.

(b) Still thirsty, the Man of Steel repeats his attempt on the Moon, which has no atmosphere. Find the difference between the water levels inside and outside the straw.

2007-11-20 02:49:53 · 5 answers · asked by ricahrd l 1

I bought a plug-in pest repellent. It claims to only cost pennies a month to use. I was wondering if anyone knew how to calculate it. The provider we use scottish power and the device claims to be 7.5watts , but doesn't have any amp/voltage figures on it.
It'll be on constantly, how much will it cost?
Also, does anyone know if these things are any good? It's a Viatek dual technology one that uses electromagnetic and ultrasonic technology

2007-11-20 02:32:03 · 4 answers · asked by Anonymous

a rope is used to pull a 10 kg block across the floor with an acceleration of 3 m/s2. if frictional force acting on the block is 50 N. what is the tension on the rope?

thanks

2007-11-20 00:29:39 · 4 answers · asked by sahar 1

1)Calculate the water pressure at the base of Hoover Damn. the depth of water behing the dam is 220m.(Neglect the pressure due to atmosphere.)
2)The top floor of a building is 30 m above the basement. Calculate how much greater the water pressure is in the basement compared with the pressure at the top floor.
3)An 8.6-kg piece of metal displaces 1 liter of water when submerged. Calculate its density.
4)A 4.7-kg piece of metal displaces 0.6 litrt of water when submerged. Calculate its density.
5)A one-cubic centimeter cube has sides 1 cm in length. What is the length of the sides of a cube of volume two cubic centimeters?
6)Consider eigth one-cubic-centimeter sugar cubes stacked two-by-two to form a single bigger cube.What will be the volume of the combined cube?How does its surface area compare to the total surface area of the eigth seperate cubes?

2007-11-19 23:47:14 · 2 answers · asked by jealousy 1

2007-11-19 23:43:17 · 2 answers · asked by RITCHELLE G 1

Suppose a 10,000,000kg ship has a length of 160m while its breadth is 25m. Estimate how deep the ship sinks assuming the bottom to be rectangular with dimensions 25m by 160m. The ship is in the sea. please answer...

2007-11-19 23:33:57 · 3 answers · asked by Meww 1

2007-11-19 21:49:25 · 4 answers · asked by Caressa Joy C 1

2007-11-19 18:44:43 · 19 answers · asked by Anonymous

a roller coaster reaches the top of the steepest hill with a speed of 6 km/h. It then descends the hill, which is at an average angle of 45 degrees and is 45.0 m long. What will its speed be when it reaches the bottom. Assume (mu)k = 0.12

answer: 23 m/s (85 km/h)

2007-11-19 17:49:31 · 2 answers · asked by Anonymous

A vertical spring with k = 480 N/m is standing on the ground. You are holding a 5.1 kg block just above the spring, not quite touching it.

(a) How far does the spring compress if you let go of the block suddenly?

(b) How far does the spring compress if you slowly lower the block to the point where you can remove your hand without disturbing it?

(c) Why do your answer differ?

2007-11-19 17:38:18 · 2 answers · asked by Anonymous

Using a highly sensitive parabolic sound collector, Tom records the frequency of a tuning fork as it drops into the Grand Canyon. He drops the vibrating tuning fork from rest at t=0. He records a frequency of 1653.0 Hz at t=4.870 s. What is the natural frequency of the tuning fork? Use Vsound=343.0 m/s.

anyone have any equations that relate these values?
thank you

2007-11-19 17:11:36 · 1 answers · asked by Zmik 3

2007-11-19 16:44:48 · 3 answers · asked by Deepa 2

2007-11-19 16:35:28 · 2 answers · asked by I want my two dollars? 3

Down in a cave below the surface of the earth there is:

a) more gravity than at the earth's surface
b) less gravity than at the earth's surface
c) the same gravity as at the surface

Assume the earth's density is the same all the way through. Of course it isn't. But simplistic idealized situations must be thoroughly understood before details can be appreciated.

2007-11-19 16:20:39 · 6 answers · asked by ? 6

what is momentum?

2007-11-19 16:03:55 · 5 answers · asked by Anonymous

A 50kg pilot comes out of a vertical dive in a circular arc such that at the bottom of the arc her upward acceleration is 8.5g.

What is the magnitude of the force exerted by the airplane seat on the pilot at the bottom of the arc?

If the speed of the plane is 345 km/h, what is the radius of the circular arc?

You don't have to do all the math, I just have no idea where to even begin!

If you could help me out, it would be greatly appreciated!

Thanks!

2007-11-19 16:02:23 · 2 answers · asked by Jackie 2

I have a packet that I've answered all by 6 questions (Out of 82). I'm unsure of what formula to use. It would be greatly appreciated if someone could walk me through how to do this particular problem?

Example:
"Using right angles"

6. An ancient Egyptian named Fred is standing 400 meters away from the center of a pyramid. He looks up 37 degrees to the top of the pyramid. How tall is the pyramid?

I'm a bit confused.

2007-11-19 15:38:12 · 2 answers · asked by Anonymous