Answer:
The unfiltered polluted water is not clear and is yellowish in color. The filtered polluted water is clear with a little bit of yellow color. The pH readings are beyond the range in which organisms can grow. Based on these observations, I can conclude that even though water may look clean, it could actually not be clean or it can still be harmful to living things.
No, education actually increased during the Renaissance. It was a time where people were discovering the philosophical nature of things, and were putting it into writing and such. The Renaissance was a time period where more and more people considered introspective ideas and more people studied topics such as art, science, mathematics, technology, music, and warfare.
There are a number of ways to reduce friction:
Make the surfaces smoother. Rough surfaces produce more friction and smooth surfaces reduce friction. Some swimmers wear suits to reduce underwater resistance. These suits mimic the smooth skin of sharks.
Lubrication is another way to make a surface smoother. A lubricant is a slippery substance designed to reduce the friction between surfaces. You might use oil to stop a door from squeaking - the oil reduces the friction in the hinge. Water can be used as a lubricant - think of how a floor becomes slippery after it has been mopped.
Make the object more streamlined. A streamline shape is one that allows air or water to flow around it easily, offering the least resistance. Compare a boxy old car with a new car that has a rounded shape, allowing it to move with less effort.
Reduce the forces acting on the surfaces. The stronger the forces acting on the surfaces, the higher the friction, so reducing the forces would reduce the friction. If you apply the handbrake when you try to drive a car, the car will have a lot of difficulty moving because of the force immobilising (stopping the movement of) the wheels. If you release the handbrake, the wheels will move more freely because there is no extra force acting on them.
Reduce the contact between the surfaces. Have you ever tried to roll a cube? Spheres are the best shape for reducing friction because very little of a spherical object is in contact with the other surface. Several types of wheels, such as skateboard wheels, contain small spheres called ball bearings to reduce the friction between the moving parts. You can witness the effect of ball bearings by comparing the friction between sliding a book on a table and then doing the same, but using marbles between the book and the surface of the table. Notice how the marbles act as ball bearings, reducing the friction.
Answer:
Slab pull is the theory of plate movement which relies on the weight of the subducting crust.
Explanation:
Plate movement are the measure of motion of tectonic plates. As it is known that our earth crust is composed of different sizes of tectonic plates. So these plates can move depending upon the pressure exerting on it. So slab pull is one of the theories existing with plate movement. In this case, the movement of the plates occur due to the weight of the subducting crust. The subducting crust is the boundary between tectonic plates. So depending upon their weights, the slab pull theory works.
