To solve this problem we will apply the concepts related to the Doppler Effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other.
Mathematically it can be described as
Where,
v = Speed of sound
f' = Reflected frequency
f = Emitted Frequency
= Speed of the object
Assuming that the speed of the medium is the speed of sound of 343m / s, we will then have that:
Answer:
<h2>Mass of 1 Kg and 2 Kg, 1 meters apart.</h2>Explanation:
The gravitational force is defined as
By definition, the gravitational force depends directly on the product of the masses and indirectly on the distance between the masses, which means the further they are, the less gravitational force would be. And, the greater the masses, the greater the gravitational force.
Among the options, the pair that would have the greatest gravitational force is Mass of 1 Kg and 2 Kg, with 1 meter between them.
Notice that the last choice includes the same masses but with a greater distance between them, that means it would be a weaker graviational force.
Therefore, the right answer is the second choice.