Answer:
Apparent frequency increases for Bob and decreases for Jill.
Explanation:
Doppler effect refers to the apparent change in frequency when there is relative motion between source and the listener. When the source and listener move closer, the apparent frequency heard by the listener increases. And when the source and listener move away from each other, the apparent frequency heard by the listener decreases.
Thus, when the emergency vehicle approaches Bob, the apparent frequency of the siren increases. It moves away from Jill, the apparent frequency heard by the Jill decreases.
The correct option is B.
A water shed refers to an area of land which serves as channel for rainfall and supply other bodies of water connected with it with water. The amount of water in the watershed determines the quantity of water that will be passed to the water bodies that are connected to the watershed.
A model is usually made in order to use it to forecast or predict a certain thing. A watershed model can be used to predict the amount of floods and drought at a particular location.<span />
<h2>If the distance between Earth and moon is increased , the gravitational force will decrease by a proportional amount .</h2><h2>The iron filings sprinkle around the magnet are arranged in regular pattern . The reason for this is that magnet can attract magnetic substances through various materials .</h2>
Explanation:
If the distance between Earth and moon is increased , the gravitational force will decrease by a proportional amount .
The iron filings sprinkle around the magnet are arranged in regular pattern . The reason for this is that magnet can attract magnetic substances through various materials .
Scientific method is a process wherein there is a common end result at the end of each milestone of the research. This is to improve the problem which was intended to be realized at the beginning of conducting or applying scientific method. The feedback loop is the part of the model which allows for continuous improvement of the method, for each result there may be atleast known and observed result analysis which is feedback to a step or the whole process for the betterment of the cycle.