Physics - April 2007

1. Imagine you are looking at an oncoming car through Johannes Kepler's telescope, What would be odd about the image? What could you do to modify the design to correct the oddity ? (Info: Keplers telescope was the first refracting telescope and used convex lenses for both the objective and eyepiece lens.

2. Under what circumstances would the oddity observed not matter?

2007-04-16 09:09:49 · 3 answers · asked by Anonymous

Initially, the capacitor in a series LC circuit
is charged. A switch is closed, allowing the
capacitor to discharge, and 0.3 micros later the
energy stored in the capacitor is one-fourth
its initial value.
Find the inductance if the capacitance is
7 pF. Answer in units of H.

2007-04-16 08:18:51 · 3 answers · asked by john s 1

2007-04-16 06:59:20 · 2 answers · asked by shamone78 1

The drawing shows a skateboarder moving at 5.4 m/s along a horizontal section of track that is slanted upward by 48 degrees above the horizontal at its end. Find his maximum height H above the end of the track.

http://img152.imageshack.us/img152/9967/ddasdqi5.jpg

2007-04-16 05:32:22 · 2 answers · asked by twiztedweb 2

A 60-degrees cone filled with water was brought to rotation
around it vertical axis with period of rataion 2s and then stopped.
The water remaing inside the cone was poured into cylindrical well
of diameter 1m and the depth of water in the well turned out to be 3m.

What is the value of accelaration g?
(answer in closed form, please)

2007-04-16 04:51:25 · 4 answers · asked by Alexander 6

2007-04-16 04:33:18 · 7 answers · asked by badal_007_cool 1

2007-04-16 04:28:05 · 4 answers · asked by BL 5

any proof scientifically that they existed????

2007-04-16 04:03:15 · 9 answers · asked by Covenanted 2

What work is done when 5.0 C is moved through an electric potential difference of 1.5 V?

2007-04-16 03:25:15 · 4 answers · asked by Jeff D 1

A voltmeter reads 500 V across two charged, parallel plates that are 0.020 m apart. What is the electric field between them?

2007-04-16 03:23:55 · 1 answers · asked by Jeff D 1

2007-04-16 03:15:37 · 12 answers · asked by attsoftwarefrog 1

2007-04-16 03:15:12 · 8 answers · asked by Anonymous

2007-04-16 03:13:56 · 1 answers · asked by Anonymous

A teacher has a glass jar with a tight fitting lid. She unscrews the lid, puts serveral lumps of ice into the jar and then seals the lid tightly. After a short time, water droplets form on the outside of the jar. She asks the class to explain how the water comes to be there. Several pupils say that it comes from the ice.

2007-04-16 03:11:56 · 9 answers · asked by Habiba 1

I saw something on tv the other day where a guy used a red flashlight to look at a map at night, explaining that the red causes you not to lose your night vision. I'm wondering if it's the same concept with alarm clocks. If so, what is it about the color red?

2007-04-16 02:40:03 · 7 answers · asked by Thom 5

can we design black light ????????????????????????

2007-04-16 01:54:28 · 9 answers · asked by Anonymous

I am doing an experiment (demo) for physics and my teacher wants us to choose something really awesome that has to do with electricity. But all the ones i see on the internet are boring, like a battery out of a potato. Does anyone have a crazy idea for me?! :D:D Thank you.

2007-04-16 01:50:43 · 4 answers · asked by somegirl 2

Is it effected by the atom in some quantum way (ie in a way that can only be described using quantum theory) or is it like light passing though air and explicable using classical theory.

2007-04-16 00:38:51 · 3 answers · asked by anthonypaullloyd 5

2007-04-15 23:32:54 · 8 answers · asked by Anonymous

refer to the case of the bird sitting on the live wire if you wish

2007-04-15 20:46:24 · 14 answers · asked by paw 1

a) copper

b)teakwood

c)glass

d)ebonite

2007-04-15 20:39:59 · 12 answers · asked by ARJUN M 1

Has to do with expansion and contraction. And why does water expand when it freezes into ice? Detailed explanations please.

2007-04-15 20:27:29 · 6 answers · asked by SkyeSkyeSkyeBlue 2

A high-speed flywheel in a motor is spinning at 500 when a power failure suddenly occurs. The flywheel has mass 36.0 and diameter 75.0 . The power is off for 34.0 and during this time the flywheel slows due to friction in its axle bearings. During the time the power is off, the flywheel makes 180 complete revolutions.

At what rate is the flywheel spinning when the power comes back on?

How long after the beginning of the power failure would it have taken the flywheel to stop if the power had not come back on?

How many revolutions would the wheel have made during this time?

2007-04-15 20:27:08 · 2 answers · asked by A.J. 1

A bubble with a volume of 1.00 cm^3 forms at the bottom of a lake that is 20 m deep. The temperature at the bottom of the lake is 20°C. The bubble rises to the surface where the water temperature is 30°C. Assume that the bubble is small enough that its temperature always matches that of its surroundings. What is the volume of the bubble just before it breaks the surface of the water? Ignore surface tension.

I thought this question involves the equation..
(P1V1)/T1=(P2V2)/T2
but I can't seem to find the right answer using this..

any suggestions/help?? thank you so much!!

2007-04-15 19:47:38 · 2 answers · asked by Anonymous

As we know it time is calculated at 24 hours in a day but I watched a tv program saying if time was calculated to the mili second there would actualy be 25 hours in a day it all had to do with the Sun or something like that Can anybody throw some light on this

2007-04-15 19:41:57 · 9 answers · asked by alan b 1

we know that a particle moves with the speed of light or more than the speed of light then its mass will be greater than the mass of universe.So why is not with electron?

2007-04-15 19:20:35 · 5 answers · asked by mudit 1

A ball of mass is attached to a string of length . It is being swung in a vertical circle with enough speed so that the string remains taut throughout the ball's motion. Assume that the ball travels freely in this vertical circle with negligible loss of total mechanical energy. To avoid confusion, take the upward direction to be positive throughout the problem. At the top and bottom of the vertical circle, label the ball's speeds Vt and Vb, and label the corresponding tensions in the string Tt and Tb*Tt. and Tb have magnitudes Tt and Tb.


Find Tb - Tt the difference between the magnitude of the tension in the string at the bottom relative to that at the top of the circle.
Express the difference in tension in terms of and . The quantities and should not appear in your final answer.

2007-04-15 19:03:25 · 2 answers · asked by SimonP 1

8 All bodies dropped together fall to the ground in the same amount of time. But if
two spheres roll down an inclined plane, one may take more time than the other.
Explain why.

2007-04-15 18:29:51 · 4 answers · asked by hafsa a 1

2007-04-15 18:29:29 · 1 answers · asked by sam_power746 1

Does the speed of sound depend on air temerature?

2007-04-15 17:07:50 · 9 answers · asked by llamaslyr 2