So far, we know two equations of uniformly varied motion that allow us to associate speed or displacement with time spent.

It becomes practical to find a function in which it is possible to know the speed of a piece of furniture without the time being known.

For this, we will use the two time functions we already know:

(1)

(2)

Isolating *t* in 1):

Replacing *t *in (2) we will have:

Reducing to a common denominator:

Example:

(UFPE) A bullet that moves at a scaling speed of 200m / s as it penetrates a block of wood fixed on a wall is slowed to a stop. How long did the bullet take to move within the block if the total distance traveled inside was equal to 10cm?

*Although the problem requires the time that the bullet took, for any of the time functions, we need to have acceleration, to calculate it using the Torricelli equation.*

*Note that the units were passed to the SI (10cm = 0.1m)*

*From there, you can calculate the time spent:*