Physics - June 2007

Tesla-Man Out of Time, pgs. 45-61 and ff. (the big white edition).

2007-06-25 14:57:56 · 4 answers · asked by comedycatalyst 2

physics wise( not gravity)

2007-06-25 14:56:49 · 7 answers · asked by piggy 1

Is this equation dimensionally correct? ( use the SI unit analysis to find out)

2007-06-25 14:36:56 · 2 answers · asked by Josh Muller 1

What influence does an observer have?

Please explain in detail; I'm a bit confused here...

2007-06-25 14:36:31 · 8 answers · asked by LUCKY3 6

A 2150-kg truck is traveling along a staight, level road at a constant speed of 55.0 km/h when the driver removes his foot from the accelerator. After 21.0 s, the truck's speed is 33.0 km/h. What is the magnitude of the average net force acting on the truck during the 21.0 s interval?

2007-06-25 14:28:06 · 2 answers · asked by Tam 1

Suppose you wish to whirl a pail full of water in a vertical circle without spilling any of its contents. If your arm is 0.91 m long (shoulder to fist) and the distance from the handle to the surface of the water is 17.0 cm, what minimum speed is required?

2007-06-25 14:27:55 · 5 answers · asked by long t 2

A diver releases an air bubble of volume 2.0 cm³ from a depth of 15 m below the surface of the lake, where the temperature in 7.0°C. What is the volume of the bubble when it reaches just below the surface of the law, where the temperature is 20°C.

I know that the answer is 5.1 cm³, but what are the steps to reach the answer?

2007-06-25 14:14:22 · 2 answers · asked by Concerned 1

A 10 kg baby sits on a three-legged stool. The diameter of each of the stool's round feet is 1.9 cm. A 60 kg adult sits on a four-legged chair that has four circular feet, each with a diameter of 5.8 cm. Who applies the greater pressure to the floor and by how much?

An extra _______N/m2 of pressure was applied to the floor by

2007-06-25 13:52:22 · 3 answers · asked by Ciel S 1

a 220 kg speedboat is negotiating a circular turn (radius = 52m) around a buoy. during the turn the engine causes a net tangential force of magnitue 550 N to be applied to the boat. the initial tangential speed of the boat going into the turn is 5.0 m/s
(a) find the tangential acceleration
(b) after the boat is 2.0 s into the turn, find the centripetal acceleration

2007-06-25 13:46:41 · 3 answers · asked by lub1210 1

a ferris wheel rotates at an angular velocity of 0.24 rad/s. starting from rest, it reaches its operating speed with an average angular acceleration of 0.030 rad/s^2. how long does it take the wheel to come up to operating speed?

2007-06-25 13:29:01 · 1 answers · asked by lub1210 1

Whereas, mass (also source of a universal interaction, namely gravitation) can theoritically vary between m0 and infinity according to the energy of the particle.

2007-06-25 13:00:15 · 4 answers · asked by Anonymous

A bicycle has wheels of radius 0.29 m. Each wheel has a rotational inertia of 0.079 kgm2 about its axle. The total mass of the bicycle including the wheels and the rider is 78 kg. When coasting at constant speed, what fraction of the total kinetic energy of the bicycle (including rider) is the rotational kinetic energy of the wheels?

2007-06-25 12:50:57 · 3 answers · asked by salvnjc4ever 1

I'm not exactly sure for how long there have been microwaves sold with metallic surfaces -in- them (as in the same space where the food gets cooked), but I know they exist, and have often been curious as to the details of their success.

2007-06-25 12:45:32 · 3 answers · asked by uncleclover 5

This happened about six months ago. The electricity went off in my apartment for a minute or two, then came back on. Before the electricity went off, my answering machine showed 0 messages. After the electricity went back on, my answering machine showed 2 messages????? The circuit breakers are in my apartment and all were in the on position. Today, the electricity went off for a few seconds, then came back on. What could account for the incident with the answering machine incident? How is this possible? Why wouldn't the answering machine show 0? And no one called and left messages during the time the electricity was off.

2007-06-25 12:34:07 · 5 answers · asked by Anonymous

Hi Im writing a program but don't worry about the coding in you answer: lets say I drop a ball in a perfect vacuum how would you determine the following (in order of importance too):
The bounce back velocity (and how it looses energy as it travels against the force of gravity)

The energy lost to friction (theres some kinetic energy equation I was pretty sure. thank you!

2007-06-25 12:34:00 · 3 answers · asked by Adam S 2

A 13 m ladder whose weight is 185 N is placed against a smooth vertical wall. A person whose weight is 953 N stands on the ladder. The foot of the ladder rests on the floor 2.99 m from the wall. Calculate the force exerted by the wall. Answer in units of N.

2007-06-25 12:21:40 · 2 answers · asked by Anonymous

Can space be subject to infinite regression? Can there always be something smaller? Does a zero dimension really exist in space, or just time?

I thought of this question by thinking about an object between two perfectly parallel mirrors. Does an infinite series of images appear? Is this the same as the above question?

2007-06-25 11:47:43 · 3 answers · asked by Trevin M 2

You hang a heavy ball with a mass of 35 kg from a gold rod 3 m long by 1.9 mm by 2.6 mm. You measure the stretch of the rod, and find that the rod stretched 0.002653 m.
Using these experimental data, what value of Young's modulus do you get?
Y = ? N/m2.
The atomic mass of gold is 197 g/mole, and the density of gold is 19.3 g/cm3.
Using this information along with the measured value of Young's modulus, calculate the speed of sound in gold.
v = ? m/s.

2007-06-25 11:43:24 · 5 answers · asked by Ashley 2

Been trying to get my head around the concept of the singularity. What are the implications to humans of smarter than human machines? I don't see how a superior intelligence could be submissive to inferior being i.e. humans. Will we really be able to download our minds onto computers and, in effect live forever? Its all very complicated.......

2007-06-25 11:40:08 · 5 answers · asked by Anonymous

Or would the innertube be too heavy.

2007-06-25 11:29:06 · 8 answers · asked by charming_imogen 2

2007-06-25 10:08:43 · 14 answers · asked by Anonymous

I know I have to use f= ma but im not exactly sure how and I need to study for a final.. Can someone please help??



A wheel of radius 27 cm, mass 3kg and moment of inertia 0.10935 kg m^2 is mounted on a frictionless, horizontal axle. A light cord wrapped around the wheel supports an object of mass 1.9 kg. The acceleration of gravity is 9.8 m/s^2. Find the tension T in the cord. Answer in units of N.


b) what is the angular acceleration of the wheel? answer in units of rad/s^2??

2007-06-25 09:51:10 · 1 answers · asked by Anonymous

How come you guys don't know or don't agree that Einstein's equation E = mc^2 come from Newton's equations? Einstein really combined the two equations of forces of Newton's to create his equation. The two equations of Newton's are F = ma and the Unversal Gravitation. Einstein put them together and did a little Math and came up with his equation E = mc^2. How come you guys don't know that?

2007-06-25 09:05:18 · 6 answers · asked by Anonymous

An air bubble with a diameter of 0.001 mm is released underwater at a depth of 15m. How large will the air bubble's diameter be at the surface? (There is an increase of 1 atm for every 10.3 m in depth in water; for a sphere, V= 4/3 x 3.14 x r^3. there is already 1 atm at the surface)

How do you solve this problem?

2007-06-25 08:58:50 · 6 answers · asked by Alexander 6

I'm looking for websites and books

Thanks

2007-06-25 08:36:46 · 10 answers · asked by Marylou 1

I have asked this question once and found it was not possible due to the laws of physics..But now I think that I have found a way to make it work.
First of all, can the energy be harnessed from the ocean by moving the water from high pressure to low pressure? No. For example if one was to put a straight pipe from the surface of the ocean down deep into the ocean, where the pressure is much high, nothing would happen. This is because of the laws of physics, the water would sit there because gravity is forcing it to stay there and the pressure is the same as if there was no pipe.
Now heres my new idea to this: If one was to put an long funneled pipe that was smaller at the surface and wider at the bottom in the same position, would the pressure at the bottom be forced up? I believe yes because the pipe would take pressure off of the top of the pipe, and the pressure at the bottom would remain the same, it would cause the water to flow to the surface where it could be used to make energy.

2007-06-25 08:27:26 · 8 answers · asked by maK 2

Hi everyone, why do smart people often study Calculus? I studied Calculus already, I saw it was not so important, but why smart kids or smart peole study Calculus in the Universities? Is Calculus important? Is it applicable to our daily life or in our world?

2007-06-25 08:24:38 · 6 answers · asked by Anonymous

2007-06-25 07:49:19 · 5 answers · asked by ? 5

Resistor, R=20 Ω and a capacitor C=200 µF are in a series circuit of alternating current with a voltage of U=120 V and a frequency of ƒ=60 Hz. What is the current that flows through the circuit? What are the voltage drops across the resistor and the capacitor?

2007-06-25 07:33:08 · 4 answers · asked by LesJerLayne 2

A battery (9.284 V) is connected to a resistor (9856 ohms) and a capacitor (15.73 mcF). Calculate the charge Q(t) on the capacitor if initially the stored charge was zero. Show your work please, if you want to be chosen a best answer.

The diagram can be found in the following link:

http://www.geocities.com/trunks11111/charge.jpg

2007-06-25 05:11:30 · 3 answers · asked by Nate-dawg 2