# Terminal Velocity Given Acceleration at Instantaneous Velocity

## Homework Statement

This is a repost of a homework like question. The previous thread I did not understand.
In the assumption that drag is proportional to velocity, and when v = 20 m/s, a = 7.35 m/s^2, find the terminal velocity.

## Homework Equations

The thread stated that the equation most relevant would be ma = mg - kv.

## The Attempt at a Solution

I substituted all know values to make m(7.35) = m(9.8) - k(20), and attempted to solve, but the answer is 40 m/s.

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verty
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How far did you get? Did you get stuck anywhere? It is too soon to give a hint, not enough has been done.

How far did you get? Did you get stuck anywhere? It is too soon to give a hint, not enough has been done.
None of that information is needed. The initial question is that it is dropped from a large height. The only information given is the information proveded (v and a).

Never mind. I solved it by not replacing ma with 0 but by dividing by m first and replacing v with v^2.

In these types of problems, when is v or v^2 used?