the equation y=-16t2+120 can be used to represent the fruits height above the ground, where t represent time ,in seconds, after she threw the apple
Well, actually she seems to have dropped it from 120 feet up or threw it horizontally.
If she threw it with any initial vertical speed Vi the equation would have been:
y = -16 t^2 + Vi t + 120
16 is about 1/2 of g in English units.
In general
y = -(1/2) g t^2 + Vi t + Hi
BUT
you did not ask any question.
Y = 120 - 16t^2 = 0 When the fruit hits gnd.
120 - 16t^2 = 0,
16t^2 = 120,
t = 2.74 s. = Time required for fruit to hit gnd.
To determine the height of the fruit above the ground at a specific time, you can use the equation y = -16t^2 + 120, where y represents the height and t represents time in seconds.
To find the height above the ground at a particular time, substitute that value of t into the equation. Here's how you can do it:
1. Identify the specific time (t) you're interested in.
2. Replace t in the equation y = -16t^2 + 120 with the value you identified.
3. Calculate the equation based on the value you substituted for t.
4. The result will be the height above the ground at the specific time.
For example, let's say you want to find the height of the fruit after 3 seconds. You would substitute t = 3 into the equation:
y = -16(3)^2 + 120
y = -16(9) + 120
y = -144 + 120
y = -24
In this case, the height of the fruit above the ground after 3 seconds would be -24 units. Please note that since the equation has a negative coefficient (-16), the height decreases over time.