A force of 100N moves a body on a horizontal frictionless surface when I. Friction force exerted on the body is less than 100N
II. Friction force exerted on the body is more than 100N
III. None of these
IV. Both of I and II

The metal wire in an incandescent lightbulb glows when the light is switched on and stops glowing when it is switched off. this simple process iswhich kind of a change? a.a physical changeb. a chemical changec. a nuclear changed. an ionic change

What elements are found in the inner and out core of the earth? the correct layers of earth's interior from the top to the center? what is the unwanted material that is removed from a mine called? how much stronger is an earthquake that registers 5 on the richter as opposed to 2? what occurs at a convergence plate boundary? the majority of the the earth's rock what is the most common element found in the earth's crust? what element is found in pyrite that contributes to acid mine drainage? why must mining companies post bond prior to permitting? how are bacteria being used in treating effluent from mines? what is a problem of acid mine drainage in rivers and soils? what do tectonic plates move on? why is gold smelting so damaging? how are artesian wells formed? where is dammed water colder than the river it flows into? what is one of the problems of uncontained aqueducts? what is the largest use of industrial water? underground sand and gravel formations that can store water? what type of water test measure acidity? which type of water test for cloudiness from suspended solids? what water test measures the amount of calcium and magnesium? these are all problems of coal power plants all of the following are advantages of riparian lands along rivers what type of water would be the warmest and have the least amount of dissolved oxygen? the zone of aeration is

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?