A pebble is dropped from the edge of a tall cliff into the ocean. The pebble's height above the ocean in feet can be modeled by the expression 400−16t2, where t is the time in seconds after the pebble is released.What does the quantity 16t2 represent in the expression?Choices:(A)the height in feet of the pebble above the ocean after t seconds(B)the distance in feet the pebble has fallen after t seconds(C)the time in seconds it takes for the pebble to fall t feet(D)the time in seconds it takes for the pebble to reach a height of t feet
Q. A pebble is dropped from the edge of a tall cliff into the ocean. The pebble's height above the ocean in feet can be modeled by the expression 400−16t2, where t is the time in seconds after the pebble is released.What does the quantity 16t2 represent in the expression?Choices:(A)the height in feet of the pebble above the ocean after t seconds(B)the distance in feet the pebble has fallen after t seconds(C)the time in seconds it takes for the pebble to fall t feet(D)the time in seconds it takes for the pebble to reach a height of t feet
Initial Height Explanation: The expression for the pebble's height is 400−16t2. The 400 represents the initial height of the pebble above the ocean.
Distance Fallen Calculation: The term 16t2 is subtracted from 400, which suggests it represents the distance the pebble has fallen after t seconds, due to gravity.
Acceleration Due to Gravity: Gravity causes objects to accelerate downwards, so the distance fallen over time is related to the acceleration due to gravity, which is 32 feet per second squared. The term 16t2 is half of this acceleration, indicating it's part of the formula for distance fallen under gravity: d=21⋅g⋅t2.
Verification of Term: Since 16 is half of 32, the term 16t2 correctly represents the distance fallen due to gravity after t seconds. This matches choice (B).
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