(Punctuation omitted.) Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 SE2d 546) (1993) and "a plaintiff must prove that the defendant's negligence was both the `cause in fact' and the `proximate cause' of the injury." Atlanta Obstetrics c. Group v. Coleman, 260 Ga. 569 ( 398 SE2d 16) (1990).

When reviewing whether the trial court erred in granting a motion for judgment n.o.v. on the issue of causation, we must be guided by these principles: "Negligence is not to be presumed, but is a matter for affirmative proof." Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 S.E.2d 546) (1993). "To recover damages in a tort action, a plaintiff must prove that the defendant's negligence was both the `cause in fact' and the `proximate cause' of the injury."

" (Punctuation omitted.) Cagle v. Ameagle Contractors, Inc., 209 Ga. App. 712, 712-713 ( 434 S.E.2d 546) (1993). So construed, the evidence shows that on April 13, 1993, around 5:30 p.m., Cantrell was traveling north on Georgia Highway 61, and Bearden was traveling south.

Even in rear-end collisions, "[n]egligence is not to be presumed, but is a matter for affirmative proof." Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 S.E.2d 546) (1993). Accordingly, the trial court did not err in giving the charge as it represents an accurate statement of abstract principles of law.

(Citations and punctuation omitted.) Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 S.E.2d 546) (1993). Evidence that Ms. Baxter increased her speed to more than 40 mph, but not more than 50 or 55 mph, prior to driving over the dips and irregularities in the roadway does not show negligence on her part without some further evidence of what the speed limit was for that area of the roadway or that such increase in speed was somehow negligent.

Whether or not the following or approaching from the rear vehicle in a rear-end collision case has exercised ordinary care to avoid the collision is usually a jury question. Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 S.E.2d 546). "Just how close to a vehicle in the lead a following vehicle, ought, in the exercise of ordinary care, be driven, just what precautions a driver of such a vehicle must in the exercise of ordinary care take to avoid colliding with a leading vehicle which slows, stops, or swerves in front of him, . . . may not be laid down in any hard and fast or general rule. In each case except where reasonable minds may not differ, what due care required, and whether it was exercised, is for the jury.

Bell v. Leatherwood, 206 Ga. App. 550, 551 ( 425 S.E.2d 679). The fact that when she saw Hitchcock's vehicle in some position before her she accelerated and swerved into the center turn lane instead of applying brakes is not "affirmative proof" (id.) of negligence on her part, in view of the undisputable facts that Hitchcock entered her lane of travel when he had mistakenly thought he could safely make the turn and mistakenly did not know the John Doe vehicle was traveling in the turn lane. Ordinarily it might be to invade the province of the jury (see Cagle v. Ameagle Contractors, 209 Ga. App. 712, 713 ( 434 S.E.2d 546)) to make such a conclusion, but the evidence demands a conclusion that Hitchcock negligently ascertained he could enter the highway safely, and Hitchcock has cited to us no evidence from which a jury could reasonably find that McPhail's only non-negligent choice in the circumstances of this case was to apply her brakes. That is, at best the jury could only speculate that in the exigent circumstances negligently created by Hitchcock, defendant McPhail's decision to swerve into the center lane was "affirmative negligence" which was comparatively greater than Hitchcock's proven negligence so as possibly to entitle him to an award of damages from her.

(Punctuation omitted.) Cagle v. Ameagle Contractors, 209 Ga. App. 712 ( 434 S.E.2d 546) (1993). A driver has no right to assume that the road ahead is clear and has a duty to maintain a lookout for potential hazards.