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1 year ago

I would appreciate your help

Physics

1 answer:

Degger [83]1 year ago

7 0

Answer:

22. C. Pz > Py > Px

23. B. 5.0 × 10⁴Pa

24. B. Upward thrust exerted by the liquid

25. B. The volume of the object immersed in the liquid decreases

26. D. When a body is wholly or partially immersed it experiences upthrust equal to the weight of the fluid displaced

Explanation:

22. The more you go deeper into the sea, the more the pressure of the water increases pushing down on you.

The reason why salt water is very dense is that when the salt dissolves in the water, it adds to the mass of the water, which makes the water more denser.

Due to this, we can assume that the water pressure exerted on the fish will be greater beneath the sea than the lake at the same depth.

Answer: C. Pz > Py > Px

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23.

Given:

Density of water = 1000 kg m⁻³

Atmospheric pressure at sea level, Patm = 1.0 × 10⁵ Pa]

Depth of water in sea = 5m

To find the pressure exerted by the water on the fish, we use the formula: P = hpg

P = pressure

h = height or depth of water

p = density of water

g = gravitational field strength

We are given the depth and density, but not the gravitational field strength

Gravitational Field Strength: Measures how much gravity there is

And since we live on earth, the gravitational field strength is 10 N/kg

Depth, h = 5m

Density, ρ = 1000 kg/m³

Gravitational Field Strength, g = 10 N/kg

Now we substitute these into the formula:

P = hpg

P = (5)(1000)(10)

Multiply 5 and 1000 to get 5000

P = 5000 × 10

Multiply 5000 and 10 to get 50000

P = 50000Pa

↓

P = 5.0 × 10⁴Pa

Answer: B. 5.0 × 10⁴Pa

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24. When a body is fully or partly immersed in a liquid, it undergoes an apparent loss in its weight due to upward thrust exerted by the liquid.

The upward thrust is the same as the weight of the fluid being displaced by an object.

Answer: B. Upward thrust exerted by the liquid

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25.

When you add common salt to water it becomes denser, which can increase the mass and volume of the water. Due to water becoming denser, it can make an object thats less dense float. Also, density and volume are inversely proportional to each other, meaning that when density increases, volume decreases.

Answer: B. The volume of the object immersed in the liquid decreases.

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26.

Achimede's principle states that:

Answer: D. When a body is wholly or partially immersed it experiences upthrust equal to the weight of the fluid displaced.

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2 years ago

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The mechanical energy of the air per unit mass is the specific kinetic energy of the air that is calculated using: $\frac{1}{2} V^2$ where V is the velocity of the air.
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6 0

2 years ago

I would appreciate your help​

I would appreciate your help