The value of R3 is A) 10 Ω
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Sound wave needs medium to travel
as energy which travels in this wave is because of transfer from one particle to another particle
If there is no medium then energy can not be transferred and sound wave will not travel
so in vacuum we can not listen sound
similarly here air is removed it means there is no medium inside the jar to travel the sound and hence we can not hear it
Option B is correct
Without air, the sound waves cannot travel to the ear.
Answer: The coefficient of static friction is 3.85 and The coefficient of kinetic friction is 2.8
Explanation:
in the attachment
Answer:
W =1562.53 N
Explanation:
It is given that,
Radius of the aluminium ball, r = 24 cm = 0.24 m
The density of Aluminium, 
We need to find the thrust and the force. The mass of the liquid displaced is given by :

V is volume
Weight of the displaced liquid
W = mg

So,

So, the thrust and the force is 1562.53 N.