# Mechanics - Initial Value Reduction

The acceleration of a marble in a certain fluid is proportional to the speed of the marble squared and is given in SI units) by a=-3.00 v^2 for v greater than 0. If the marble enters this fluid with a speed of 1.20 m/s, how long will it take before the marble's speed is reduced to half of its initial value?

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#### Solution Preview

Another way of writing a is dv/dt. So we have the equation:

dv/dt = -3*v^2

Divide both sides by v^2 and multiply ...

#### Solution Summary

The solution is given in an equation with short descriptions explaining how to do it.

$2.19