Exposure = how long the shutter is opened. The longer it is opened more blur will appear if the objects are in motion (That is why at weddings and similar occasions the photographer asks people to stand still). If you’re taking snapshot of motionless object than it is better to use longer exposure for that will enable more time for light to reach whatever it reaches in digital cameras
Amount of aperture opening should be set according to distance of object but it also can define focus on object or on background. As the amount of aperture opening decreases depth sharpness increases and vice-versa. Also, as the focused object distances from the camera the depth sharpness increases.
If you want to emphasize the speed of the car in motion than you can use longer exposure & larger aperture while following the car with camera and taking snapshot (without stopping to click). If you want to catch as much of the background as possible you should reduce exposure and reduce aperture to minimum still following the car and taking snapshot without stopping.
You can do all this without following the car (fixed position of the camera) but than the blur will be greater than with following procedure described previously.
It is the opening of the shutter that begins and ends process of taking snapshot. As soon as the shutter starts opening the light starts penetrating into camera and the moment the shutter is closed the process of taking snapshot is over. Time of the exposure = speed of shutter you're mentioning.
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BTW 1, I know that I can edit posts but that seams like cheating to me because I don’t know if someone has already read it before I’ve edited it. Now I’ve done it for I mixed exposure and aperture in original post.
BTW 2, I'm not photographer also, so stand to be corrected