Typically during thunderstorms most lightning strikes carry a negative electric charge; only a few carry a positive charge. Thun
derstorms with unusually high proportions of positive-charge strikes tend to occur in smoky areas near forest fires. The fact that smoke carries positively charged smoke particles into the air above a fire suggests the hypothesis that the extra positive strikes occur because of the presence of such particles in the storm clouds. Which of the following, if discovered to be true, most seriously undermines the hypothesis? (A) Other kinds of rare lightning also occur with unusually high frequency in the vicinity of forest fires.
(B) The positive-charge strikes that occur near forest fires tend to be no more powerful than positive strikes normally are.
(C) A positive-charge strike is as likely to start a forest fire as a negative charge strike is.
(D) Thunderstorms that occur in drifting clouds of smoke have extra positive-charge strikes weeks after the charge of the smoke particles has dissipated.
(E) The total number of lightning strikes during a thunderstorm is usually within the normal range in the vicinity of a forest fire.
Considering the hypothesis elaborated in this comprehension, it's given that areas that tend to lie near forest fires usually have extra positive strikes since smoke carries positively charged particles. In rudimentary term, this states that occurrence of positively charged particles will result in extra positive strikes.
Option (D) states that occurrence of extra positive strikes will be there even weeks after the charge of smoke particles have been dissociated.
Therefore this option, most seriously undermines the hypothesis.
The equal and opposite force is the force of the stone's gravity pulling up on thy Earth.
<u>Explanation</u>:
When someone tosses a stone off a cliff, the force of gravity of Earth pulls down and theforce of the stone's gravity pulls up on the Earth due to the equal and opposite reaction exerted between the Earth and the stone.
In Newton's third law, two important features are present. One is the force exerted on two bodies will have the same magnitude but opposite direction. The other feature is force is acting on two different objects.
This exerted force is equal in magnitude but opposite in direction whereas the gravity exerts a downward force on a stone and upward force on an Earth which is opposite in direction.
