The phrase "affects the velocity" is correct and usable in written English.
It can be used in contexts discussing factors that influence speed or rate of movement in various fields such as physics, engineering, or even in everyday situations.
Example: "The friction between the surfaces affects the velocity of the sliding object."
Alternatives: "influences the speed" or "impacts the rate".
Four summers later, in 1899, he wrote to his classmate Mileva Marić (later his wife), "I had a good idea for investigating the way in which a body's relative motion with respect to the luminiferous ether affects the velocity of the propagation of light in transparent bodies".
The sphere size affects the velocity but not the overall behavior.
Our results show that the interfacial imperfection strongly affects the velocity of the interfacial shear waves.
The degree of slope affects the velocity of overland flow and runoff, infiltration rate and thus soil transportation.
This affects the velocity of the ions because X+ (H+) ions gain(loose) energy while moving along against) the convective electric field.
The results show large gas accumulation even at very low air volume fraction (0.05%), which significantly affects the velocity field and the pressure recovery of the diffuser.
The pain Hernández reported has not affected the velocity on his fastball, although it has caused discomfort at times when he throws his curveball and slider.
That tentativeness has sapped his efficiency and, he surmised, affected the velocity and movement on his two-seam fastball, his signature pitch.
Instead, something unidentified is affecting the velocity of spacecraft at their closest approach to our planet.
Since the control action is defined as acceleration or deceleration only, actions can only affect the velocity.
The geometry of the specimen and the current stress state at any given point of the specimen affect the velocity of a 'pointer' running along these two curves.
