The characteristic that will be affected by increasing the speed of an object from 30 meters per second (m/s) to 40 meters per second (m/s) is kinetic energy.
Kinetic energy (KE) is given by the formula:
\[ KE = \frac{1}{2} mv^2 \]
where \( m \) is the mass of the object and \( v \) is its velocity. As the velocity increases, the kinetic energy increases with the square of the velocity. Thus, increasing the speed from 30 m/s to 40 m/s will result in a significant increase in the kinetic energy of the object.