Answer:
The Hydrostatic force is 
The location of pressure center is 
Explanation:
From the question we are told that
The height of the gate is 
The weight of the gate is 
The height of the water is 
The density of water is 
Note used 
for height of water and height of gate immersed by water since both have the same value
The area of the gate immersed in water is mathematically represented as
substituting values
The hydrostatic force is mathematically represented as
Where
So
The center of pressure is mathematically represented as
Where 
is the moment of inertia of the gate which mathematically represented as
The is the height of gate immersed in water
Thus
Force = (mass) x (acceleration) Newton's second law of motion.
Force = (2 kg) x (3 m/s²) = 6 newtons.
I would say Option B) because Option C) is wrong since matter cannot be created. A closed system does not exchange matter so it's not Option D). Since an island is an isolated area, Option A) is wrong.
Answer: d. 8.25 m/s
Explanation:
We are given that Current= 5 m/s in j direction
Velocity= 8 m/s i + 3 m/s j
Now, we have to find Jada's speed with respect to the water.
First we find Jada's velocity with respect to water
v= (8 i + 3 j) - (5 j)
v= 8i - 2 j
To find the speed, we take the magnitude of this velocity vector we have
|v|= 
|v|= 
= 8.246 m/s
which comes out to be around = 8.25 m/s
So option d is correct.
