A droplet of water drips from the end of a stalactite high up on the roof of a cave. The height of the water droplet above the cave floor in meters can be modeled by the expression 22−4.9t2, where t is the time in seconds after the water droplet begins to fall.What does the quantity 4.9t2 represent in the expression?Choices:(A)the distance in meters the water droplet has fallen after t seconds(B)the time in seconds it takes for the water droplet to reach a height of t meters(C)the time in seconds it takes for the water droplet to fall t meters(D)the height in meters of the water droplet above the cave floor after t seconds
Q. A droplet of water drips from the end of a stalactite high up on the roof of a cave. The height of the water droplet above the cave floor in meters can be modeled by the expression 22−4.9t2, where t is the time in seconds after the water droplet begins to fall.What does the quantity 4.9t2 represent in the expression?Choices:(A)the distance in meters the water droplet has fallen after t seconds(B)the time in seconds it takes for the water droplet to reach a height of t meters(C)the time in seconds it takes for the water droplet to fall t meters(D)the height in meters of the water droplet above the cave floor after t seconds
Height Expression Analysis: The expression for the height of the water droplet is 22−4.9t2. We know that the initial height is 22 meters, so the term 4.9t2 must represent the distance fallen after t seconds, because as time increases, the height decreases.
Derivation of 4.9t2: The term 4.9t2 is derived from the physics equation for the distance fallen under gravity, which is (1/2)gt2, where g is the acceleration due to gravity (9.8m/s2). So, 4.9 is half of 9.8, which confirms that 4.9t2 is the distance fallen.
Confirmation of Distance Fallen: Since 4.9t2 represents the distance fallen, it matches with choice (A) the distance in meters the water droplet has fallen after t seconds.
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