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3 years ago

a 55.0 kg person having a denity of 1010 kg/m^3 is underwater. What is the net force acting on the person?

Physics

1 answer:

bija089 [108]3 years ago

6 0

Answer:

The net force acting on the person is 5.34 N acting upwards

Explanation:

The information given are;

Mass of the person = 55.0 kg

Density of the person = 1010 kg/m³

Body volume of the person = Mass/Density = 55/1010 = 0.0545 m³

Weight of the person = Mass × Gravity = 55 × 9.81 = 539.55 N↓

Where the density of water = 1000 kg/m³, we have;

Upthrust = weight of the water displaced = Mass of the water displaced × Gravity

Mass of the water displaced = Density of water × Volume of the water

Mass of the water displaced = Density of water × Body volume of the person

= 1000 × 0.0545 = 54.5 kg

The Upthrust = 54.5 × 9.81 = 534.21 N↑

Given that the net force, $F_{Net}$ acting is the sum of the mass of forces acting on the person which are the weight acting downward and the upthrust acting upwards

We have;

F(Net) = 534.21↑ - 539.55↓ = 5.34 N↑

The net force acting on the person = 5.34 N upwards.

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EleoNora [17]

Answer:

130.165636364°C

Explanation:

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4 years ago

Which of the following statements about electric field lines associated with electric charges is false? Electric field lines can

Tcecarenko [31]

Answer:

The false statement is 'Electric field lines form closed loops'.

Explanation:

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3 years ago

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skelet666 [1.2K]

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3 years ago

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Answer:

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Explanation:

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This means that for constant electric potential the electric field must be zero:

$V(\vec{r}) = k$

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$\vec{E} (\vec{r}) = - (0,0,0)$

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3 years ago