A 300 Kg Ball Is Released from Rest and Is Acted

question 20

Multiple Choice

A 30.0 kg ball is released from rest and is acted upon by a net force of -1.40  10¹⁶ r ^-2 (the force pulls the ball towards r = 0) .The ball starts from rest at an initial position of r_i = 6.39  10⁶ m and moves under the influence of the force to a final position of r_f= 6.38  10⁶.What is the kinetic energy of the ball when it reaches its final position,r_f?

• A)2.94  10⁶ J.
• B)9.22  10⁶ J.
• C)1.58  10⁶ J.
• D)3.75  10⁶ J.
• E)3.43  10⁶ J.

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Definitions:

Compound Microscope

An optical instrument consisting of a series of lenses that magnify objects in steps; used for detailed observation of microorganisms and cells.

Substage Illuminator

A light source located beneath the stage of a microscope, used to illuminate the specimen from below.

Iris Diaphragm

An adjustable aperture used in optical instruments, like microscopes and cameras, to control the amount of light passing through the lens.

Condenser

A device used to condense vapor into liquid, widely used in laboratory equipment, air conditioning, and power plants.