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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.
In fresh water sound waves travel at 1497m/s at 25 degrees, I'll assume that's the characteristics of the water.
If it's 0.01s then you need to divide the speed by 100 to get the, 14.97, however it gets there and back in that time so you need to halve it.
<u>7.485m</u>
The temperature of a balloon is
lowered with liquid nitrogen. The balloon appears to deflate because the gas in
the balloon lost energy and condensed. The answer is letter D.
Answer:
The work done on the box is 80 J.
Explanation:
Given that,
Weight of box = 40 N
Distance = 2 meter
We need to calculate the work done
Using formula of work done


Where, x = distance
mg = weight
Put the value into the formula



Hence, The work done on the box is 80 J.
Answer:

Explanation:
Given that,
Mass of a person, m = 84 kg
The person is standing at a top of Mt. Everest at an altitude of 8848 m
We need to find the gravitational potential energy of the person. We know that the gravitational potential energy is possessed due to the position of an object. It is given by :
E = mgh, g is the acceleration due to gravity

So, the gravitational potential energy of the person is 