<u>Answer :</u>
(a) d = 0.25 m
(b) d = 0.5 m
<u>Explanation :</u>
It is given that,
Frequency of sound waves, f = 686 Hz
Speed of sound wave at
is, v = 343 m/s
(1) Perfectly destructive interference occurs when the path difference is half integral multiple of wavelength i.e.
........(1)
Velocity of sound wave is given by :




Hence, when the speakers are in phase the smallest distance between the speakers for which the interference of the sound waves is perfectly destructive is 0.25 m.
(2) For constructive interference, the path difference is integral multiple of wavelengths i.e.
( n = integers )
Let n = 1
So, 


Hence, the smallest distance between the speakers for which the interference of the sound waves is maximum constructive is 0.5 m.
Answer:
Explanation:
Suppose v is the initial velocity and
is the angle of inclination
distance traveled in vertical direction in t=1 s
When gravity is present

where 



here initial velocity is v\sin \theta [/tex] so


In absence of gravity



Answer and explanation:
A correct option is an option (B).
The electrical force between two charges is given as,

The electrical force is directly proportional to the product of two charges. Thus Force will depend on two charges irrespective of their signs.
Option (A) is incorrect because if charges are opposite, the value of force will not be zero. It will be -ve.
Option (C) is incorrect because the force is directly proportional to the product of charges, it depends on the amount of charge.
Option (D) is also incorrect because the force in inversly proportional to the distance between two charges. Thus, if the distance between two charges is increased, the force between two charges will decrease.
Concllusion:
The correct option is option (B).
If the rabbits died out, the other organisms would be likely to die. (If that were their main source of food.)
producer- something that produces food for other organisms (and is consumed). ex.grass
primary consumers- eat the producers and like first. ex. rabbit
secondary consumer- eats the primary consumers
Scavenger - is basically an organism that scavenges for food ex. vulture.
good luck!