John Throws a Rock Down with Speed 20 M/s from the Top

question 10

Multiple Choice

John throws a rock down with speed 20 m/s from the top of a 30-m tower.If g = 9.8 m/s² and air resistance is negligible,what is the rock's speed just as it hits the ground?

• A) 12 m/s
• B) 28 m/s
• C) 31 m/s
• D) 78 m/s

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Definitions:

Hemoglobin

A protein in red blood cells that carries oxygen from the lungs to the body’s tissues and returns carbon dioxide from the tissues back to the lungs.

Brain Activity

The functioning of the brain as it engages in various cognitive, sensory, and motor tasks, typically measured by various neuroimaging techniques.

Hormones

Chemical messengers produced by the endocrine glands that regulate various bodily functions and processes.

Neurotransmitters

Chemical messengers that transmit signals across a chemical synapse, from one neuron (nerve cell) to another 'target' neuron, muscle cell, or gland cell.