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sardarzada11 Tuesday, May 09, 2006 08:47 AM

Give Scientific Reasons
 
1. Why does your voice sound different to you on a recording?

A- When you hear yourself speak regularly, the sound waves emanate through the tissue, bone, and other material, which changes its sound
B- When you hear yourself speak regularly, the sound waves bounce off who you are talking to, which changes its sound.
C- The speakers of the cassette recorder distort the sound of your recorded voice
D- I don't know


2. Do you move faster when swimming under the water or half-submerged?

A- You move faster under the water
B- You move faster when half submerged
C- I don't know

3. You are sitting in a baseball game in bleachers far from the field. You see the batter hit the ball and then you hear the crack of the bat. Why the delay?

A- The sound has to travel through a lot of material (all the people in the stadium) before it reaches your ear.
B- Light travels almost one million times faster than sound
C- Your brain anticipates what is going to happen visually, so you see the act a split second before it actually happens
D- You are too far away to hear the actual sound of the bat hitting the ball. What you hear is the echo of the actual sound.
E- I don't know

4. What are mirages?

A- Hallucinations of dehydrated wanderers
B- A mixture of gases that leak through fissures in the earth, mixing to create strange apparitions
C- Miniature whirlwinds blow sand in tight circles that seem to take shape from a distance
D- Optical phenomenon due to temperature differences of the surface and air directly above the surface
E- Low lying clouds
F- I don't know

5. Why does one sometimes have red-eyes in photographs?

A- The rays of the sun bounce off the lens of the camera, projecting a reddish glow into the eyes of those photographed
B- An ineffective flash doesn't allow enough light for the actual eye color to be recorded in the photo
C- A flash that is too glaring often makes people blink at the same time the shutter snaps. Therefore, the subjects eyes are merely blurred, though it appears red in the actual photo
D- The pupil doesn't have enough time to constrict and the picture records the reflection of the red retina in the back of the eye
E- I don't know

6. It is estimated that there are about 100 occurrences of lightning throughout the world each second. How many of these strike ground?

A- 75
B- 50
C- 25
D- 5
E- I don't know

7. Why is the moon small when it is high overhead in the sky, and large when it is near the horizon?


A- Near the horizon, the brain scales the size of the moon to trees and buildings
B- The moon is actually much closer when it is near the horizon, and thus appears larger.
C- The physical act of rolling the eyes upwards (towards the sky) encourages the brain to interpret objects to be smaller than they are.
D- When the moon is viewed near the horizon, one is actually viewing its reflection against the earth's ozone layer. This image is a shrunken version of the actual moon
E- I don't know

8. Which of the following has been known to curdle milk?

A- Sugar
B- Thunderstorms
C- Extremely loud music
D- Acidic soil
E- I don't know

9. Can pearls be found within mussels?

A- Yes
B- No
C- I don't know

10. What would happen if you soaked a raw egg in vinegar for 24 hours?

A- The yolk would turn green
B- It would disintegrate completely
C- The shell would turn rubbery
D- The shell would split perfectly in two
E- I don't know



Regards,
Sardarzada

Mr Ghayas Tuesday, May 09, 2006 10:29 AM

1. [B]Question[/B]: Why does your voice sound different to you on a recording?
[B]Answer[/B]: When you hear yourself speak regularly, the sound waves emanate through the tissue, bone, and other material, which changes its sound.

2. [B]Question[/B]: Do you move faster when swimming under the water or half-submerged?
[B]Answer[/B]: You move faster under the water

3. [B]Question[/B]: You are sitting in a baseball game in bleachers far from the field. You see the batter hit the ball and then you hear the crack of the bat. Why the delay?
[B]Answer[/B]: Light travels almost one million times faster than sound.

4. [B]Question[/B]: What are mirages?
[B]Answer[/B]: Optical phenomenon due to temperature differences of the surface and air directly above the surface

5. [B]Question[/B]: Why does one sometimes have red-eyes in photographs?
[B]Answer[/B]: The pupil doesn't have enough time to constrict and the picture records the reflection of the red retina in the back of the eye.

6. [B]Question[/B]: It is estimated that there are about 100 occurrences of lightning throughout the world each second. How many of these strike ground?
[B]Answer[/B]: 25

7. [B]Question[/B]: Why is the moon small when it is high overhead in the sky, and large when it is near the horizon?
[B]Answer[/B]: Near the horizon, the brain scales the size of the moon to trees and buildings.

8. [B]Question[/B]: Which of the following has been known to curdle milk?
[B]Answer[/B]: Thunderstorms

9. [B]Question[/B]: Can pearls be found within mussels?
[B]Answer[/B]: Yes

10. [B]Question[/B]: What would happen if you soaked a raw egg in vinegar for 24 hours?
[B]Answer[/B]: The shell would turn rubbery

Viqar Tuesday, March 06, 2007 04:24 PM

answer the question
 
kindly relpy this question as i found in previous everyday science papers

"Why man holes are round"

Pls reply and thanks...

Last Island Tuesday, March 06, 2007 04:37 PM

Manholes need to be covered. Manholes, which interconnect underground sewerage pipes, and serve as a point of entry for cleaning the pipes, are located at every major sewer pipe junction, and are capped with round manhole covers. The reason for the circular construction of these covers is, quite simply, that covers of any other shape would fall through the manholes by virtue of their varying diameters. Circular manhole covers do not vary in width, or in diameter, as is the case with these other shapes, thus remaining in place despite the street traffic running roughshod over them.

Manufacturers craft the manhole covers together with the smaller sized lip, upon which they rest, at the same time to ensure a tightly sealed fit. Additionally, the manufacture of circular manhole covers is easier and more accurate than the manufacture of covers of any other shape. Lastly, round manhole covers, once removed, require less lifting and less manpower, as their shape allows them to be rolled.

Najabat Thursday, April 05, 2007 04:50 PM

Does the hump on camels hold water???
 
We heard since childhood that camels store water in their hump but its not very right.....Actually a camel's hump is a giant [B]mound of fat[/B]. In a healthy, well-fed camel, the hump can weigh as much as 80 pounds (35 kilograms)! Human beings and most animals store their fat mixed in with muscle tissue or in a layer right beneath the skin. Camels are the only animals with a hump.

The hump allows a camel to survive an extremely long time (up to two weeks) without food if need be. Because camels typically live in the desert, where food can be scarce for long stretches, this is important.

A camel uses about 5 gallons (20 liters) of water a day in the summer. However, a camel can lose up to 25 gallons (100 liters) of water from its body tissues without ill effects. [B]One thing that a camel can do to conserve water is to handle large body-temperature swings[/B]. A camel might start the day at 94 degrees F and allow its temperature to rise as high as 105 degrees F. Only at the upper end of this range does it need to sweat to prevent overheating. When you compare this temperature range to the range the human body can handle (where only a 2 degree rise indicates illness).Thts y people say camels the "Aircraft of Deserts".

rauf butt Saturday, April 14, 2007 05:54 PM

why does the sky look blue?
 
Assalaam o alikum.
my name is ABDUL RAOUF BUTT. I am preparing for CSS.
i wana know why does the sky look blue?please help me because i did not found a comprehensive answer in any book.
thanks.

At Ur Own Risk Saturday, April 14, 2007 09:24 PM

The sky looks blue because earth's atmosphere scatters sunlight. The sky is not actually blue, it only looks that way. It does not always look blue and even when it does it's not quite the same color or the same brightness everywhere. To scatter is to strew about aimlessly or to disperse. The atmosphere does that to light, but it scatters some colors better than others Sunlight is actually all the colors of the rainbow mixed together. The visible spectrum is the colors red, yellow, green, blue, indigo, and violet. Sunlight reaches us in the form of waves and each color consists of waves of a slightly different frequency. Of visible light, red has the lowest frequency and violet has the highest frequency. The frequencies of the other colors fall in between. At the end of the 19th century an English scientist, Lord Rayleigh, discovered that small particles do not scatter light in the same way as large particles. Air molecules are extremely small and scatter the high frequency violet and blue better than the low frequency red. Scattered sunlight contains more violet and blue than red but we see blue better than violet so the sky looks blue. At least it looks blue most of the time. At sunrise and sunset the sky is red, orange, or yellow. Rayleigh scattering is responsible, but the light passes through more air before it reaches our eyes. By the time the sunlight reaches us, scattering has removed the high frequencies to make blue skies for people on the part of earth where the sun is higher in the sky. Red light remains because it is scattered less. Big droplets of water which collect around bits of dust in the air to form a cloud or fog are too big for Rayleigh scattering. They scatter all colors equally so the clouds they form look white. Smaller water droplets which collect around dust or pollutants in the air form a yellowish haze.. Rayleigh scattering essentially absorbs the incoming light, then re-radiates it in all directions. We then see this scattered light coming to us from all directions. The scattered light is not only blue. It contains small amounts of the other colors as well, so the sky is not just blue. It is sky blue.

Reference:([url]http://home.honolulu.hawaii.edu/~rickb/SciColumns/BlueSky.08Apr95.html[/url])

Venus Saturday, May 26, 2007 05:08 PM

Scientific Reasons
 
plz answer these questions


1# Why water boils quicker on mountains?
2# Why rainbow is produced in the sky after rainfall and sunlight?
3# Why water remains cool in Earthenware pitcher?
4# Why milk is considered as an ideal food?
5# Why meat takes longer to cook on the mountains?
6# Why ica and salt mixture is used as a freezing agent in manual ice-cream maker?
7# Why greenhouse operators paint their glass roof white in summer?

prissygirl Sunday, May 27, 2007 09:48 PM

plz just go throughout the everyday science portion.....u will get the answers of most of ur questions...they r available

Venus Monday, May 28, 2007 08:00 PM

I have already gone through it and couldnt find what i m searching for . Plz help.


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