- #1
autodidude
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- 0
If the function of a falling ball is s = 4t^2 where s is distance and t is time then to find the instantaneous speed you'd use:
s + k = 4(t + h)^2
k = additional distance, h = additional time
So if t=3 then you get:
s + k = 4(3+h)^2
s + k = 4(9+6h+h^2)
s + k = 36 + 24h + 4h^2
Subtract s from both sides to get additional distance
k = 24h + 4h^2
Then when you divide by h to obtain the velocity and you let h approach 0, you get 24 the instantaneous speed at t=3, my question is essentially why 24 is the instantaneous speed, how did it we get that from the equation (not how as in we plugged numbers in and that's what we got), but its relationship to the other variables and the constant and what it means physically...know what I'm saying?
By the way, this example is from Morris Kline's Calculus text, I just changed the constant to 4 to make easier to work out in my head
s + k = 4(t + h)^2
k = additional distance, h = additional time
So if t=3 then you get:
s + k = 4(3+h)^2
s + k = 4(9+6h+h^2)
s + k = 36 + 24h + 4h^2
Subtract s from both sides to get additional distance
k = 24h + 4h^2
Then when you divide by h to obtain the velocity and you let h approach 0, you get 24 the instantaneous speed at t=3, my question is essentially why 24 is the instantaneous speed, how did it we get that from the equation (not how as in we plugged numbers in and that's what we got), but its relationship to the other variables and the constant and what it means physically...know what I'm saying?
By the way, this example is from Morris Kline's Calculus text, I just changed the constant to 4 to make easier to work out in my head