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3 years ago

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A 400 kg satellite is in a circular orbit at an altitude of 500 km above the Earth's surface. Because of air friction, the satel

lite eventually falls to the Earth's surface, where it hits the ground with a speed of 1.60 km/s. How much energy was transformed into internal energy by means of air friction

1 answer:

scoundrel [369]3 years ago

8 0

Answer:

E = 1.45 x 10⁹ J = 1.45 GJ

Explanation:

According to the law of conservation of energy:

Potential Energy Lost by Satellite = Kinetic Energy + Internal Energy

$mgh = \frac{1}{2} mv^2 + E\\\\E = mgh - \frac{1}{2} mv^2$

where,

E = Internal Energy = ?

m = mass = 400 kg

g = acceleration due to gravity = 9.81 m/s²

h = height = 500 km = 500000 m

v = speed on ground = 1.6 km/s = 1600 m/s

Therefore,

$E = (400\ kg)(9.81\ m/s^2)(500000\ m)-\frac{1}{2} (400\ kg)(1600\ m/s)^2\\E = 1.962\ x\ 10^9\ J - 0.512\ x\ 10^9\ J$

<u>E = 1.45 x 10⁹ J = 1.45 GJ</u>

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A small steel wire of diameter 1.0 mm is connected to an oscillator and is under a tension of 7.5 N. The frequency of the oscill

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Answer:

a

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b

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Explanation:

From the question we are told that

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This is mathematically evaluated as

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Where a is the area of the the wire = $\pi r^2 = (3.142 * 0.5*10^{-3})^2 =7.855*10^{-7}m^2$

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This is mathematically evaluated as

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This is mathematically evaluated as

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Where T is the tension with a given value of $7.5N$

$v = \sqrt{\frac{7.5}{6.162*10^{-3}} }$

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What are 3 different forces that act on objects on the earth ΩvΩ

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A force is a push or pull acting upon an object as a result of its interaction with another object. There are a variety of types of forces. a variety of force types were placed into two broad category headings on the basis of whether the force resulted from the contact or non-contact of the two interacting objects.

Contact Forces

Action-at-a-Distance Forces

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Gravitational Force
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