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2 years ago

Pls help me l will make it brainlest

Physics

2 answers:

emmasim [6.3K]2 years ago

7 0

Calculate the value of the area expansion of a steel rod of lenght 4cm at 20°c after heating attains another length of 9cm at 70°c.

Area = 0.02

Area Expansity = $0.0 {4}^{ - 1}$

nikklg [1K]2 years ago

3 0

Answer:

0.04 °C⁻¹

Explanation:

First, we need to calculate linear expansivity, then after finding that value, we can move on to finding the area expansivity.

=============================================================

Finding Linear Expansivity :

⇒ α = Final length - Original length / (Original length × ΔT)

⇒ α = 9 - 4 / (4 × 70 - 20)

⇒ α = 5 / 5 × 50

⇒ α = 0.02

============================================================

Finding Area Expansivity :

⇒ Area Expansivity = 2 × Linear Expansivity

⇒ β = 2 × α

⇒ β = 2 × 0.02

⇒ β = 0.04 °C⁻¹

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drek231 [11]

Answer:

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Explanation:

The initial force of gravity is:

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and we know that $F_{1}=\frac{Gm_{1}m_{2}}{r^2}$

so the new force of gravity is:

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The force of gravity after you double the mass and the distance is half of the initial force.

3 0

3 years ago

In braking an automobile, the friction between the brake drums and brake shoes converts the car's kinetic energy into heat. If a

satela [25.4K]

To solve this problem it is necessary to apply the concepts related to energy conservation.

In this case the kinetic energy is given as

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Where,

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$Q = mC_p \Delta T \rightarrow 4Q = 4mC_p \Delta T$

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For conservation we have to

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3 years ago

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3 years ago

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Vlad [161]

Answer:

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3 years ago

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Zina [86]

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4 years ago

Pls help me l will make it brainlest ​

Pls help me l will make it brainlest