Find t: Solving a Physics Problem with y = 0

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The discussion focuses on solving the equation y = -4Ve^(-t/4) - 4gt + 4V for time t when y = 0, specifically in the context of a physics problem involving a golf ball. The initial steps involve substituting y = 0 and manipulating the equation, leading to the expression 1 = e^(-t/4) + gt/V. However, it is noted that logarithmic properties were misapplied in the attempted solution, as log(A+B) does not equal log(A) + log(B). The consensus is that the equation cannot be solved analytically and will require numerical methods, contingent on having a specific value for V. The thread concludes with a welcome message to the new participant.
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1. Homework Statement

Solve for t

y = -4Ve^(-t/4) - 4gt + 4V


2. Homework Equations

V = Initial Velocity
g = Gravity
t = Time

3. The Attempt at a Solution

y = 0 (Physics problem, hitting a golfball and solving for t when y = 0)

-4V = -4Ve^(-t/4) - 4gt
V = Ve^(-t/4) + gt
1 = e^(-t/4) + gt/V
0 = -t/4 + ln(gt/V)

Couldn't get further
 
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lespommes said:
3. The Attempt at a Solution

y = 0 (Physics problem, hitting a golfball and solving for t when y = 0)

-4V = -4Ve^(-t/4) - 4gt
V = Ve^(-t/4) + gt
1 = e^(-t/4) + gt/V
Looks good up to here.
0 = -t/4 + ln(gt/V)
Sorry, no, logarithms don't work that way:
log(A+B) ≠ log(A) + log(B)​

The equation
1 = e^(-t/4) + gt/V​
can't be solved analytically, and will require a numerical solution. And that would require a value for V; were you given one?

p.s. welcome to PF.
 
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