Are you asking what it means?
sound travels through a medium in mechanical waves a mechanical wave is a disturbance that moves and transports energy from one place to another through a medium
Answer:
Rise in level of fluid is 0.11 m
Rise in level of fluid in case of mercury is 0.728 cm or 7.28 mm
Solution:
As per the question:
Density of oil, 
Change in Pressure in the tank, 
Density of the mercury, 
Now,
To calculate the rise in the level of fluid inside the manometer:
We know that:
1 mmHg = 133.332 Pa
Thus

Also,

where
g = acceleration due to gravity
h = height of the fluid level

h = 0.11 m
Now, if mercury is used:


h = 0.00728 m = 7.28 mm
Answer:
271.095 m
Explanation:
✓ Let speed of sound in air that was given as (343 m/s) be represented as (Vi)
✓( speed of sound in concrete that was given as (3000 m/s ) be debited as (Vc)
✓ Let the distance travelled by the sound = s
✓duration of Time that exist between heard of sounds = 0.70s
But we know that
Time = (Distance / Speed)
✓Time it takes the sound to travel through air= s/vi = s/343
✓Time it takes the sound to travel through concrete= s/vc = s/3000
✓ (s/343) - (s/3000) = 0.70
Finding LCM and simplify
[(3000s - 343s)]/1029000 = 0.70
2657s /1029000 = 0.70
Making " s" subject of the formula
s= (1029000 × 0.70)/2657
s=720300/ 2657
s= 271.095 m
Hence, The impact took place at a distance of 271.095 m away from the person.