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: 6,400 km
Explanation:
The weight of a person is given by:
where m is the mass of the person and g is the acceleration due to gravity. While the mass does not depend on the height above the surface, the value of g does, following the formula:
where
G is the gravitational constant
M is the Earth's mass
r is the distance of the person from the Earth's center
The problem says that the person weighs 800 N at the Earth's surface, so when r=R (Earth's radius):
(1)
Now we want to find the height h above the surface at which the weight of the man is 200 N:
(2)
If we divide eq.(1) by eq.(2), we get
By solving the equation, we find:
which has two solutions:
--> negative solution, we can ignore it
--> this is our solution
Since the Earth's radius is , the person should be at
above Earth's surface.