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Science Experiments
Experiments often conducted by students to test different scientific theories and hypotheses
11,111 Questions
Definition of Biotic agents of soil erosion?
soil erosion is washing away of soil or carring away of soil from one place to another
You originally asked how long a tripod "lived," but I think you meant "last." Almost any tripod should last a lifetime with reasonable care. A few tips I can think of off the top of my head:
* Never overload it. A light tripod is not for a heavy camera. (This is a judgment call and hard to assess in words, but an example would be putting a 4x5-inch view camera on a tripod intended for a 35 mm.) * If it gets wet, carefully dry it. * Keep it lightly lubricated. * If sand or other abrasives find their way into the joints, take it apart and clean it. * Try not to cross thread the socket on your camera, which will damage both the socket and the tripod screw. * Treat it like the valuable piece of equipment it is. Don't throw it in the trunk. Place it in the trunk.
* Don't overstress the legs. They can only open up to the stops. You can bend or break a leg on even a heavily built tripod.
Take care of your tripod and it should take care of you.
What happenes when a season changes?
It is the tilt of the Earth's axis at 66.5 degrees to the ecliptic in combination with the rotation of the planet around the Sun, that are the essential parts of seasonal changes.
The first thing that needs clarification is that the tilt relative to the true North Pole and the plane of the Ecliptic, is always pointing at the same Star in outer space, no matter what the season. The ecliptic is the enclosed area traced by the Earth as it moves around the Sun and as it is ~circular, it can be divided into four quarters, each of 90 degrees. (Not to be confused with Lunar quarters which are monthly where-as these are annual.)
The easiest way to visualize this, is to put yourself on the North Star at which the Earth's North Pole points, and look back at the Ecliptic - the Earth - and the Sun. The Earth's North Pole will be pointing straight at you all the time. Unfortunately you have to choose an arbitrary "up" and I like to see the ecliptic with the top as the March equinox. That means half way between mid-summer and mid-winter for the Southern Hemisphere, and moving towards Winter.
(When looking from the North Star, the Earth is moving counter-clockwise around the Sun and this counter-clockwise direction would be reversed if we were looking outwards from the inner galaxy onto the South Pole.)
Obviously the bottom of the ecliptic is the September equinox. Half-way between mid-winter and mid-summer for the Southern Hemisphere and moving towards Summer.
90 degrees of this rotation is also called three months and three months after each of these equinoxes, each of the hemispheres will be in either Mid-Winter or Mid-Summer. So the equinoxes were either Autumnal or Spring depending in which hemisphere you live.
It is also said that the equinox is the moment at which the Sun crosses the Equator whether going North or South. This may or may not be helpful as that moment may be night or day, so saying that it occurs on a particular day is a minor misrepresentation. Not to mention it's timing relative to the International Date Line. In reality the Equator of the Earth is crossing the Ecliptic and given the 66.5 degree tilt of the Earth's axis relative to that Ecliptic, the duration of transit would very short indeed.
I offer no apologizes for supplying a description that may be beyond the comprehension of some, but it is obviously not a simple question.
Is about 1800 miles thick with temperature reaching 8000 f?
Earth's mantle is about 1,800 miles thick with an average temperature of 5400 °F
with a range of about 1,652 °F to 7,230 °F (according to Wikipedia).
How did geologists estimate the aging of rock layers before radioactivity?
The rock layers were simply assigned geologic period classifications based on index fossils. Little was know about the true age of the rock, only that they were quite old based on the appearance of the fossils compared to existing organisms, and the knowledge that sedimentary rock formation usually took great lengths of time, and that layers of sediments were mostly cyclical in nature.
How can a hypothesis be tested?
observe it ,when there is a quick reaction...compare the reactions in the problem you've been solving..
What famous experiment did Ivan Pavlov do?
Ivan Pavlov did an experiment with dogs that demonstrated that reflexes can be conditioned and supported the idea of "conditioning". His experiment is often referred to as Pavlov's Dogs. Together with his assistant, Ivan Filippovitch Tolochinov, he started this experiment in 1901.
While studying the digestive system, he focused on the signals that triggered related reactions, such as the secretion of saliva. His test subjects were dogs. He would put food on the dogs tongue and wait for salivation to occur. He noted that upon even visually seeing food, the dogs would salivate from their salivary glands at the back of their oral cavities. Saliva, as you might know is secreted so that whatever you are swallowing can move through your esophagus comfortably. It also contains salivary amylase, a polysaccharide breaking enzyme.
With this in mind, Pavlov was curious as to why, after a while of experimenting, his dogs salivated without even seeing food. What was going on?
He furthered his experiment, trying to see if perhaps his tentative hypothesis was correct. Pavlov's experiment was quite simple. He would ring a bell before showing and serving the dogs food. This pattern continued for a while.
Afterwards, he simply rang the bell. Even without the food present, the dogs salivated.
After the experiment he realized that the dogs were salivating in the very beginning because of the lab coats - every time they were fed, their food was brought by someone in a lab coat.
This famous experiment proved that animals could be trained or conditioned to expect a result for an action based on previous experiments. This is referred to as Classical or Pavlovian Conditioning.
yes It sounds like you have a good handle on this based on the question..
Which varible goes on the y axis?
Any variable (or number), can go on the y-axis, as long as it is identified as being there by a coordinate pair (or triple).
What are the steps a scientist uses in an experiment called It's nine letters the third one is an o?
Procedure
I saw a blue flash of light like a camera flash in the sky What was it?
It's possible it was what is called an Iridium Flare. [See related question]
There was one predicted for 20:23 on the 27th November at an altitude of 15o so it's quite possible that is what you saw.
See related question and link for more information.
We don't know anything about what the bob is hung with. Is it a bamboo pole ? A steel rod ?
A chain or 1/4" aluminum cable ? Is it a thin massless thread ?
It makes a difference, because the arc-period of the whole assembly depends on the length
between its center of mass and the pivot.
Since we don't know anything about the support, we'll assume it to be massless.
Also, since we don't know anything about the bob itself, we'll assume it to be a point, with no
dimensions, hanging on the end of a massless string.
Now the period depends only on the length of the string, and is the same regardless of the
mass or weight of the bob. So, removing half of the mercury from the bob has no effect on the period.
What perspective on truth seeking did Descartes and Bacon advocate?
Descartes and Bacon both advocated for skepticism and looking for the truth in a rational fashion. They both had methods of finding the truth in a logically ordered fashion that incorporated reasonable doubt.
How would you put a 2-3 mm hole into a very thin and small test tube?
Read on! You'll use these same techniques to drill glass, glass block, tile, stone, granite, wine bottles, sea glass and marble. # # Use diamond bits to drill your glass, not carbide bits. # Use diamond hole saws to drill holes 1/4" and larger or to drill holes in thick glass like glass block or wine bottles. # Use plenty of lubrication/coolant to keep your drill tip cool and the hole clean. # Use less pressure! Let your drill bit drill at it's own pace. # Start diamond hole saws at 600-900 RPM. # Start diamond drill bits at 2500-5000 RPM. If you use these 6 secrets, drilling glass and tile is quick and easy. The FAQs below should answer any other questions you might have. * http://www.drillglass.com/hehiforbe.html
What is the IUPAC name for CH3-CH2-CH2-CH2-Br?
1 - bromopropane is the IUPAC name for CH3-CH2-CH2-CH2-Br.
What changes due to the independent variable in an experiment?
The dependent variable MAY change, but it need not.
Why can a carefully placed needle float on water even though it is more dense then the water?
Because of the surface tension: the attracting force between the water molecules, which effectively causes a "skin" on the top of the water. Drop a few drops of soap in the water and the needle will sink, because the soap weakens the bond between the water's molecules.
What is the law governing food and drinks in the high school chemistry lab?
Food and drinks are not allowed in the high school chemistry lab.
In which step of a formal scientific report are observations and measurements recorded?
lol 04 science school cert
What would be a hypothesis for a lemon battery?
It depends if your doing a test such as does this _______ and this ________ materials work better than this and this, but im doing my science project and its just the lemon battery just out in the open, showing how it works, so my hypothesis is just will the lemon battery work"?,, and i would answer yes.
Hope this helps by the way if that wasn't scientific enough because im only in the 7th grade check out some websites on google:)
How was electricity discovered?
Micheal Faraday discovered the relationship between magnetic fields and electricity traveling in a wire. This led to the brilliant work of Tesla. He is the father of modern electricity. He invented the shaded pole electric motor. Still the heart of most systems today at the house or factory. Others shaped the finer details.
In 1752, Franklin is said to have performed the famous experiment of flying a kite during a thunderstorm, to which led to the discovery that lightning and electricity were somehow related. Modern scientists know this to be something of a tall tale, since being hit by lightning would have been fatal. It's likely that Franklin was actually insulated, away from the path of lightning.
Phenomenon associated with stationary or moving electric charges.
The word comes from the Greek elektron("amber"); the Greeks discovered that amber rubbed with fur attracted light objects such as feathers. Such effects due to stationary charges, or static electricity, were the first electrical phenomena to be studied. Not until the early 19th century were static electricity and electric current shown to be aspects of the same phenomenon. The discovery of the electron, which carries a charge designated as negative, showed that the various manifestations of electricity are the result of the accumulation or motion of numbers of electrons. The invention of the incandescent lightbulb (1879) and the construction of the first central D.C. power station (1881) by Thomas Alva Edison led to the rapid introduction of electric power into factories and homes. D,C, proved not to be the way to transmit power over any distance. A.C. from Teslas' inventions supplanted Edisons' equipment rapidly.
Michael Faraday, Luigi Galvani, Alessandro Volta, Andre-Marie Ampere, and Greg Ohm did work that provided the basis for modern electrical engineering.
Italian physician Girolamo Cardano returned to the subject of electricity in De Subtilitate (1550) distinguishing, perhaps for the first time, between electrical and magnetic forces. In 1600, the English scientist William Gilbert coined the modern Latin word 'electricus' from 'elektron', the Greek word for 'amber' which soon gave rise to the English word - electricity.
Otto von Guericke invented an early electrostatic generator in 1660. Other European pioneers were Robert Boyle, who in 1675 stated that electric attraction and repulsion can act across a vacuum. Stephen Grey, who in 1729 classified materials as conductors and insulators, and C. F Du Fay, who first identified the tow types of electricity that would later be called positive and negative.
Would burning diesel fuel be a chemical change?
Yes, burning diesel fuel is a chemical change because it involves a chemical reaction where the fuel reacts with oxygen in the air to produce heat, light, and new chemical compounds like carbon dioxide and water vapor. The original diesel fuel is transformed into different substances during combustion.
What kind of scale is used to measure weight?
Scales used to measure weight include: * Spring scale - measures the increased length of a spring as it stretches * Balance scale - uses a horizontal lever to compare unknown weights to that of known weights
